During the Cold War, was the Soviet military actually well organized and a serious threat to the west,
The effectiveness of the Cold War Soviet armed forces is difficult to judge, due to a lack of evidence - the Soviet Cold War forces were involved in few wars. What wars did they fight in?
Soviet intervention in the Hungarian Uprising (1956): The first round of fighting in Budapest, between the Soviet forces which were normally stationed in Hungary trying to prevent the collapse of communist rule and the revolutionaries, went badly for the Soviet forces. The Soviet forces expected, but did not receive, support from the Hungarian army. They didn't expect major resistance from the population. The fighting of 24th-28th October in Budapest demonstrated well-known difficulties of attacking in urban fighting, and the vulnerability of armoured vehicles in urban terrain. Soviet forces did much better in the second round of their intervention, from 4th November, when they attacked in much greater strength, having reinforced their original 5 divisions in Hungary to 17 divisions. The majority of the fighting was over by 9th November, with a few areas holding out until 11th November.
Warsaw Pact invasion of Czechoslovakia (1968): While some other Warsaw Pact countries participated, the invasion was about 80% Soviet. The Czechoslovak government did not prepare for the invasion, and when it occurred, there was very little armed resistance - the government kept the army out of fighting, and urged the people to not resist. (There was much non-violent resistance by the population, which continued for some months.) The main notable military event related to the question of effectiveness was the capture of Prague Ruzyně International Airport by Soviet special forces in a surprise attack, arriving on a supposedly-civilian flight making a supposedly-emergency landing justified by claimed engine trouble. This takeover of the airport was followed by large-scale reinforcement by air.
Soviet-Afghan War (1979-1989): Famed as the Soviet Union's "Vietnam", this war demonstrated (unsurprisingly) that Soviet military forces were adept at winning straightforward set-piece battles when they had overwhelming numerical and material superiority. It also demonstrated the difficulties that conventional forces faced in guerilla warfare, and the political ineptness of the initial invasion and consequent war. The invasion was intended to quickly bring relative peace to Afghanistan, and the Soviet leadership did not expect a long-term guerilla war. The Afghan government had only been in power for a short time, having risen to power in the "Saur Revolution" of 1978, when the communist (and pro-Soviet) People's Democratic Party of Afghanistan (PDPA) overthrew Mohammed Daoud Khan's non-democratic one-party authoritarian government (which had itself overthrown the democratic constitution monarchy led by his cousin and king, Mohammed Zahir Shah, in 1973). The first leader of the PDPA government embarked on an ambitious modernisation and transformation plan for Afghanistan, including radical overhaul of the Islamic-based legal system, and aiming at thorough "de-feudalisation" of Afghanistan. As many in the Soviet Union predicted, this provoked widespread unrest and resistance, which grew rapidly, and the government lost control of most of the countryside. In early 1979, Taraki requested Soviet intervention to help restore order, which was refused. However, the Soviet Union did station forces along the border. Still in 1979, Hafizullah Amin, the 2nd-most powerful person in the PDPA government, overthrew Taraki in a coup. Perhaps contrary to Amin's expectations, the open revolt against the PDPA continued. Just as Taraki had done, Amin requested Soviet intervention. This time, the Soviets agreed, and Soviet forces entered Afghanistan. Unknown to Amin, their first step in restoring order was Amin's overthrow. Amin was overthrown in a military assault on his palace, and he was replaced by Babrak Karmal, who had been 3rd-most powerful in Taraki's government. However, Amin's overthrow failed to stop the rebellion, and the Soviet forces remained for many years, propping up a deeply unpopular government. Lasting a similar time to the USA's major commitment in Vietnam, the war resulted in proportionally similar casualties to the US forces in Vietnam (the Soviet casualties were about 1/4 of the US casualties, as their force was about 1/4 the size of the US forces in Vietnam).
What can we learn from these? First, given time to prepare, the Soviet armed forces could successfully execute daring and well-planned missions (e.g., the capture of Ruzyně airport, the overthrow of Amin). Generally, organisation was good. The invasion of Czechoslovakia suffered some problems with shortages of food, water, and fuel; the invasion of Afghanistan proceeded more smoothly, despite much more difficult conditions (but also an invasion force only about 1/3 the size of the initial invasion force committed to Czechoslovakia).
However, there were also problems. Operational flexibility at lower command levels was poor - "mission command" (or "Auftragstaktik" as the US army would say in its Germanophilic moments) was far from the minds of Soviet leadership. Essentially, Auftragstaktik consists of "These are your goals; achieve them", as opposed to Befehlstaktik, "These are your orders; carry them out". Mission command places higher demands on the training of lower-level officers, NCOs, and enlisted men, and requires higher command to trust the lower levels of the command structure. Order-command (Befehlstaktik) requires more detailed planned, and obedience from the lower levels. This was nothing new - order-command had been standard Soviet practice during the Great Patriotic War (i.e., WWII).
There were also serious problems with the training, motivation, and morale of Soviet conscripts. Considering that a major part of the military experience of junior conscripts was regular beatings by the senior conscripts, this should have been no surprise. This led to poor tactical performance by conscripts, and mistrust of conscripts by Soviet command. This, in turn, led to conscripts being lied to by their commanders as the nature and dangers of their mission. In Afghanistan, poor morale and training also led to widespread atrocities and war crimes. In both Hungary and Afghanistan, they led to widespread indiscriminate use of heavy firepower despite the presence of civilians.
The fall of the Soviet Union did not end any of these problems with the armed forces, and the post-Soviet economic convulsions left fewer resources for new equipment, maintenance, and training. The Russian-Chechen wars of 1994-1996 and 1999-2000 and the following insurgency showed that all of these problems still remained, and training and morale of conscripts had perhaps become even worse. By the time of the Russo-Georgian War of 2008, high-level organisation had improved, but training remained poor, and the army still suffered from poor funding. Improved organisation allowed effective use of air power, and rapid organisation of the invasion. However, intelligence and communications were poor. The take-home message for the Russians from the Russo-Georgian War was that reforms begun in response to the wars in Chechnya still had a long way to go. The 2014 invasion of Crimea was well-planned, quickly-organised, and included successful and daring use of special forces to take key places. However, invasions against minimal or no resistance are generally easy, and reveal few problems. The Russian intervention in Syria, from 2015 and still ongoing, has been successful, but mostly limited to air power. Generally, the Russian armed forces of a few years ago still had many of the strengths and weaknesses they had inherited from the Soviet armed forces.
The 2022 Russian invasion of Ukraine once again shows the same strengths and problems.
(continued next post)
Well...this is a big question. And oh boy is that a lot of thread upvotes. Off the bat I should say that I will take a different tack from /u/wotan_weevil's answer, both in the big-picture sense - "How do we judge the effectiveness of a military in a war which never happened?" - and in certain supporting arguments. In particular, I will break my answer up chronologically because we are not talking about the same Soviet military in 1956 as we are in 1985. As their answer went up first, I will structure parts of my answer in a bit of a dialogue with theirs. For the rest, I will take you all on a stroll through the Cold War Soviet Army. With no further ado - В путь!
In some ways this question is not answerable, because that war was never fought and we can only suppose how the Soviet military might have performed. So what evidence do we have from which to suppose? Wotan has already run through several of the major military operations involving Soviet forces. However, none of these are the real deal when it comes to a serious confrontation with NATO. They are snapshots of some aspects of military performance. Critically, these are snapshots of a particular moment in time for the Soviet Armed Forces - the Soviet military of the Khruschev years is after all a totally different force from that of the Ogarkov years - and we know that the Soviets integrated the lessons of these snapshots into future planning. Therefore we will have to combine these snapshots with other analyses. Fortunately, the Cold War produced a great mass of military analysis and forecasting both from NATO and from the Soviets themselves.^(1)
It is this analysis which I will rest the majority of my argument on, integrated with information on the actual performance shown by Soviet forces in the aforementioned limited wars. This analysis will cover the correlation of forces (what is the qualitative and quantitative balance of troops and equipment); doctrine (how they planned to fight); and how well the actual force could meet doctrine (morale, training quality, industrial base). I will address Western and Soviet analyses & sources in this answer, with an obvious deference given to Soviet sources; however Western sources will be used extensively to mitigate accessibility barriers, and where these Western sources are flatly incorrect I will do my best to show exactly where the issues lie via translated Soviet sources. I believe this approach will answer for us both halves of your question: how prepared & competent was the Soviet military, and to what extent were Western assessments driven by propaganda? A rough timeline of the military balance during the Cold War will be helpful. We can periodize this as:
I will not devote much time to the period of 1945-1953. The prospects for conflict in this period were generally low, both parties were in the process of post-WW2 demobilization, force reorganization, and for the Soviets also territorial consolidation and massive rebuilding. And of course, for the first part of this period, the US had a monopoly nuclear weapons.^(2) It was clear that the lines of a new confrontation were being drawn , but aside from flashpoints like the Berlin Airlift the odds of a major war between the Soviets and the Americans at this time were low.^(3)
The second period, 1953-1960 or so, is more interesting to us. As I said in the opening to this answer, this period can be considered the start of the “nuclear revolution in military affairs”. For both the Americans and the Soviets, postwar budgetary pressures strongly incentivized cuts to conventional forces. Nuclear forces were seen as more economical, as large nuclear forces were destructive enough to deter any aggression.^(4) As Soviet Premier Khruschev stated plainly to the Supreme Soviet in a 1960 address,
Our state has a powerful rocket technology. Given the present development of military technology, military aviation and the navy have lost their former importance. This type of armament is not being reduced but replaced. Military aviation is now being almost entirely replaced by missiles. We have now sharply reduced and probably will further reduce and even halt production of bombers and other obsolete equipment. In the navy, the submarine fleet is assuming greater importance and surface ships can no longer play the role they played in the past.”^(5)
The apparently grim realities of the conventional military balance for NATO in this period, coupled with the American head start on nuclear weapons development, contributed greatly to this preference on the American side. At the time it was believed that there was as much as a 10:1 Soviet numerical advantage in Central Europe; later revelations revised this down significantly, particularly in light of the Khruschev troop cuts - a reduction of about 2.6 million troops from 1950 - 1960.^(6) We now know from Soviet sources that, following the force reduction talks at the 1955 Geneva Summit, the Soviets did withdraw 75,000 troops from the Group of Soviet Forces in Germany (GSVG), though there was some offsetting by rearmament in the East German Nationale Volksarmee. GSVG also received high priority for new equipment, such as T-10 heavy tanks in this period.^(7) I am still trying to piece together the state of morale and training in GSVG at this time, however. I have not found any memoirs or Soviet analyses which give a good indication of this. We know that at the immediate end of the war, looting and crime were rampant and there were significant issues with keeping soldiers controlled; however, demobilization remedied much of that. We know from memoirs also that for much of the Cold War, Soviet soldiers garrisoned in the USSR had all kinds of odd secondary duties such as agriculture and construction; I am curious if they were used in this manner in the occupation days, but I have no evidence either way.
None of this is to suggest that the conventional force withered on the vine. This was the era of the so-called “Zhukov reforms”, though Rodian Malinovksy and Pavel Rotmistrov probably deserve their own credit. These reforms can be seen as the Soviets doubling down on what they did best in the Second World War: Rapid, large-scale maneuver by armored and mechanized forces, albeit with new adaptations made for the nuclear battlefield. (This theme will continue in later sections.) A common description of the Red Army in the Second World War is that it was intellectually a mechanized maneuver army hamstrung by an industrial inability to mechanize. In the period of the “Zhukov reforms” this was plainly no longer the case. Soviet industry produced a colossal number of armored vehicles and trucks to support this force restructuring - for instance between the BTR-152 & BTR-40 armored troop carriers somewhere on the far side of 10,000 were built in this time period. This was along with about 16,000 T-54 medium tanks and...some difficult to determine number of T-10 heavy tanks. Maybe fewer than 2,000, maybe more than 8,000. Trucks to supply this force - somewhere in the realm of 400,000 medium and heavy cargo trucks. I’m not going to list the entire balance, but you get the idea. It was clear to Western analysts at the time (and has since been borne out as fact by Soviet documents) that whatever demobilization Soviet society as a whole had undergone, the Soviet military was getting ready for a modern war. The lessons of the Great Patriotic War were digested in minute detail, most particularly the span-of-control problems which had limited the agility of their mobile units. The Soviet command echelons in this period were filled with combat-tested generals, as well.
I'm going to break here for character limit reasons. The next portion of this answer should go up tonight.