This is not an unusual question; rather it is bound to come up in almost every discussion of Fascism – and it may appear to be, in fact, one that calls for a rather straightforward answer. Did Fascism do anything good?

Unfortunately, I feel the question is quite a lot more complex and demanding of a certain degree of painful and careful bricklaying (which I'll try to keep to an absolute minimum). In fact, I believe these sorts of question to be rather difficult to answer properly, as they carry something of a fundamental flaw. First – as De Felice was keen on pointing out, if I remember correctly – it's often quite disingenuous to ask whether a government which lasted for over twenty years (and was able to wield the largest degree of power ever in the history of Italy) did anything good. As if even the worst, most nefarious and incompetent cabal of crooks could wreck a state to such an extent to abruptly end all sorts of “good things” produced by the associated life of a community of millions of people (I mean, I suppose that one could regard that as a worst case scenario, but it's more of a cut out from bad dystopia fiction than real history). Things that, one should remember, we don't usually credit to “the government” but which we regard as almost ordinary advancement of the institutions of a properly regulated state – despite recurrent talks of “stuff that Mussolini did”, if one were to ascribe every single “advancement” (more on this point later) made during the ten years of Giolitti's political hegemony to the old liberal statesman himself, they would likely dwarf the respective achievements of Fascism. In this regard, it's worth noting that it would be wrong to credit every positive result – or to ignore the negatives – to Giolitti alone, but a similar consideration should apply to Mussolini, as he wasn't, after all, running the trains or clearing marshes all by himself.

But, from a broader perspective – and to highlight a deeper issue with the demand for an “objective” evaluation of Fascism – I would argue that a government's policies can't be evaluated abstracting from the intention and circumstances which inspired them - a position which someone may disagree with (and to an extent, there are instruments to build a thorough and comprehensive examination of every single aspect of every single policy pursued by Fascism, which at least come close to an objective picture, but are generally difficult to muster even in the context of specialized literature), but was certainly far from uncommon in contemporary evaluation of financial and social governance (see already the influential discussion in Pantaleoni, M. Contributo alla teoria del riparto delle spese pubbliche, 1883). In other words, a Government's policies are only effective in relation to their purpose (starting from the moment of allocation of foreseeable resources), and we can judge of their effectiveness only if we understand their purpose - which, to a degree at least, leads us to examine whether we agree with those intentions.

This has both an obvious and a more remote consequence in a general evaluation. The first one being: how do we evaluate policies which have what appears to be a manifest, objectively positive impact, but also a clear and undisputed purpose that most would regard negatively?

There is no way to set apart the basic elements of “welfare state” (vacations, public education, entertainment – largely overemphasized by the Regime, they did exist nonetheless) introduced by Fascism from the underlying intention to maintain and secure a degree of consensus needed to sustain the Regime's existence. Fascism did pursue and develop means for people to express themselves, but only and merely within the Regime, within the State; this expression becoming a channel for the natural process of identification in the organic collective of Fascism. There is no way to set apart the frequent, and often generous, charities supplied by Mussolini's personal secretary, and usually upon direct request, from the conscious and systematic use which Mussolini did of this instrument in order to increase his personal stature both above the institutions of the state and the party structures. You can't have one without the other.

The recurrent trope of “the trains running on schedule” is easy to dismiss on objective grounds, if one doesn't understand the almost symbolic meaning of the statement, calling back to the tense years of post war social conflict and to the much hated – at least for the “constitutional” classes – practice of public employees going on “political” strike. While the railroads and urban transportation used to be – to cite Mussolini's Popolo d'Italia - a “Bolshevism delivery service”, now that fascists had been placed in charge, institutionalizing the practice of relieving the “Bolsheviks” of their duties, no public servant would even dare interrupt service. Consider the commentary provided by the Corriere della Sera to the "legalitarian" strike of August 1^st 1922.

[…] the conduct of the railroad workers is especially insufferable. They protest to the detriment of the entire Nation, they get back at the entire Nation because of their hostility towards the fascists, they inflict a major disservice only to the vast majority of people who are extraneous to conflicts between parties, which these intolerable subversives persevere in regarding as the crude materials of their Bolshevik endeavors. First the cowardice, then the laughable soft-handedness of the Government […] couldn't produce any other result.

Indeed this result had been achieved at a substantial social cost, but with a (likely overestimated but nonetheless substantial) financial result. One can't ignore how the political significance of those measures eased a policy of systematic layoffs of railway workers; indeed, at the end of 1924 the Minister of Finances, Alberto de Stefani, could celebrate the accomplished restructuring and rationalization of public employment. As a consequence both the Railways and the Post and Telegraphs recorded (according to official data) a modest profit (176 millions and 45 millions respectively in 1924-25 – after years of impressive deficits: for instance 1,087 and 301 millions in 1919-20 and 1,431 and 506 millions in 1921-22). The substantial layoffs (46,566 and 8,621 respectively – with the total reduction of public employment amounting to 65,274 jobs cut between October 1922 and April 1924) were usually motivated, and therefore justified, besides the need to restore the state's finances, with the need to avoid disruption of public services and therefore with the removal of subversive elements.

But, again, some may argue that, in a well organized economy, producers associations underlining supposed class divisions rather than the true national unity - and therefore resulting in promoting social conflict and disrupting the fundamental functions of the organized community - should not exist. Consequently, that any manifestation internal to the production process should be classified in accordance to whether it reveals an immediate economical need (basic sustenance) or rather an ultimate political intention, and accordingly either tolerated and eased with limited assistance or strongly suppressed. Furthermore that such manifestations should be, always and under any circumstance, absolutely inadmissible for functionaries of the State. Indeed, such arguments - which I disagree with (not sure if it's worth pointing out) - were a prominent part of political debate since the early instances of labor associationism in mid to late XIX Century Italy. And the Nationalists, already in 1914 (see for instance A. Rocco's famous exposition to the national congress), essentially supported a similar line of thought. Many of those points remained central to the approach of Italian Fascism to labor organization. Now, one may regard those positions as fundamentally wrong, or merely argue on the grounds of their supposed economical ineffectiveness - which, again, is a fair argument to make, but doesn't really provide us with an ultimate answer, since one can make the exact opposite argument, and the accusation of operating under a flawed ideological premise is unlikely to deter them from doing so. In other words, if you believe certain economical policies to be a fundamental necessity to the unity of the Nation, then you are likely to regard their execution within the context of the Fascist Regime as a positive. This is, after all, what the supporters of these policies did. If you conversely believe those policies to be detrimental to the development of the Nation, or conflicting with the true underlying class interests, or fundamentally immoral, then you are likely to regard their execution as a negative. And indeed, that the situation produced by the complete shattering of the socialist (and to a lesser degree catholic) labor organization was problematic, was something that the fascists themselves had to realize, as – to cite R. Vivarelli – during late 1921-22 the new fascist associations appeared “completely inept” to ensure the maintenance of any of the achievements the workers had managed during the previous two years, unless, of course, the Government stepped in to sustain them.

While Mussolini can be defended by some by highlighting his pragmatic statesmanship of the 1920's/early 30's, Italian economic and social welfare advancements, and guiding Italy out of the Great Depression better than most countries, this is a thin veneer compared to the overall legacy of Fascism in Italy; an ideology that would eventually leave the Italian state utterly destroyed with over 500,000 Italians dead in the pursuit of territorial expansion alongside Nazi Germany. When it comes to what Fascism did for Italy, it's take it piece by piece.

The Revolutionary Fascist Party, later renamed the National Fascist Party, was founded by Mussolini in 1915 was deeply rooted in Italian Nationalism with a focus on expansion of Italy's territories in order to project strength on the world stage. Using local paramilitary squads known as Squadrismos, later the blackshirts under Mussolini's direct control, the Fascist Party used these squadrismos and blackshirts to intimidate voters and opposition parties, carrying out beatings of those who voted against the Fascists, marching on Rome in a show of force to take power in a coup, and carry out political assassinations of opposition politicians; the most notable of which was of Italian Socialist leader Giacomo Matteotii, who contested the results of the 1924 election which secured a comfortable Fascist majority.

on January 3, 1925, in response to growing public outcry from the political violence from the squadrismos and blackshirts as well as pressure from the blackshirts to crush all political opposition, Mussolini gave a speech at the Italian parliament claiming responsibility for the political violence, and essentially dared anyone from the opposition to stop him. Nobody did, and all pretense of democracy was dropped as Mussolini set up a police state, and would dismantle nearly all democratic institutions as he solidified power around himself as the head of government.

So now we've established what the Fascists did for Italy in the beginning, sending armed thugs to intimidate and assassinate opponents, resulting in the dismantling of democratic institutions in the country as the Fascists assumed near-total control of the government. Lets tackle what they did with that power, starting with the economy, and then to the main event, foreign policy.

In the aftermath of World War I, Italy suffered an extensive economic crisis marked by mass strikes, occupation of factories by workers, high inflation, and high unemployment. It went as far as the main assembly factory of FIAT having the communist red flag raised over it by occupiers. Mussolini and the Fascists main promise that allotted them popular support was their promises to stabilize the economy.

The Fascists' tackling of the economy brought mixed results, but did put a cap on the unrest of 1919/20 and brought a semblance of stability back to Italy. Mussolini's government engaged in massive deficit spending on public works programs such as endowing universities, building roads, digging canals, constructing schools, developing Italy's colonial possessions with a focus on the economically promising Eritrea, and reorganizing the railway system to 'make the trains run on time'. This was along with other grander works such as attempting to extend Rome's city limits to the sea and establish a commercial port at the capital, which was never fully realized.

Money was also invested into social welfare programs such as ensuring food assistance, infant care, unemployment benefits, wage supplements, and public housing. While these were indeed progressive policies of their time, it came at the cost of increasing deficit spending, increasing Italy's public debt from 93 billion Lire in 1922 to nearly 150 billion Lire by 1934.

A more controversial aspect of the Fascist handling of the economy is Mussolini's "Battles" of the economy, with ambitious programs such as increasing the Lire's purchasing power, dubbed the "Battle of the Lire", agricultural overhauls to increase food self-sufficiency "Battle for Grain", and land reclamation "Battle for Land". These projects saw high tariffs placed on imports and lowered tariffs on others in order to incentivize self-sufficiency as well as military armament. The battle for grain made imported food more expensive and less accessible for Italy, which still relied on food imports as it was not agriculturally self-sufficient. The Battle for the Lire however lowered the costs of imported industrial materials such as coal, oil, and steel, making military armament manufacturing cheaper in pursuit of Italy's expansionist goals. The Battle for Land was a complete economic failure, with 80,000 hectares of land reclaimed for development but later completely abandoned.

Now we move on to the crux of Fascism's legacy on Italy, it's expansionist ambitions and decent into war. The first major expansionist move was in Ethiopia in 1934-35, which border clashes and disagreements over where Italian military bases were located served as the casus belli for Italy to declare war on Ethiopia. Britain and France attempted to negotiate with Mussolini, offering him large swaths of Ethiopia but these plans fell through and the whole of Ethiopia was conquered, later subjected to a brutal repression of the native population by the Italian military under Field Marshal Rodolfo Graziani. This war diplomatically isolated Fascist Italy with international sanctions imposed on the country for its aggression. Other aggressive actions included support for Francisco Franco's Spanish Nationalists, with volunteers and material sent to fight in the Spanish Civil War, as well as Italy's quick takeover of Albania in 1939, with the country capitulating within a week.

Diplomatically isolated from the western democracies of Britain and France, and Mussolini's ever grander vision for Italy to become a new Roman Empire, dominant over North Africa and the Mediterranean, the country entered an alliance with the other expansion-minded power in Europe, Nazi Germany.

Italy entered WWII formally in reaction to the Fall of France in June of 1940. While Italy's military was in no realistic shape to fight a global war after Mussolini's previous expansionist ventures in Ethiopia, Spain, and Albania, he remained convinced that France and Britain were practically defeated already by Germany with the fall of France. As the war escalated further and further, with the Soviet Union and the United States as enemies, the Italian army and industry simply could not compete in terms of production of war material and couldn't bring the resources needed to effectively fight this war. With the island of Sicily fallen and an Allied invasion of the Italian mainland imminent, the Italian government and King Vittorio Emmanuel III moved to remove Mussolini from power and surrender to the Allies. This prompted Hitler to invade and seize as much of Italy as possible, establishing a Fascist puppet state with Mussolini reinstalled as its leader. The Italian Social Republic was marked by ever more brutal oppression of the population. Widespread executions of those accused of disloyalty, terror campaigns where blackshirts would invade the homes of civilians, and the deportation of Italian Jews to Germany where they perished in the Holocaust. By April of 1945, Italy was completely ruined. The country turned into a battlefield and almost all economic capacity in the country was in ruins.

As for the question, What did Mussolini and Fascism do in Italy, in much more simpler terms, it ruined Italy.

For further reading, I'd say to check out Italian fascism: its origins & development by Alexander J. De Grand, and Modern Italy: A Political History by Denis Smith