I think it says something about Reddit that its first reaction to the Allied bombing of Germany is to think about some dinosaur bones, and not the 635,000 people that died as a result of it, but I digress.

Adam Tooze, in The Wages of Destruction: The Making and Breaking of the Nazi Economy argued that one of the most decisive moments of the war was RAF Bomber Command's attacks on the Ruhr in the spring of 1943. Up to then, the RAF had launched some large raids, including the first thousand-plane raid on Cologne on the night of 30 May 1942. This period included the Cabinet's dehousing paper and the RAF's area bombing directive that committed Bomber Command to attacking German cities in general with the aim of killing, displacing and demoralising the German population, in particular industrial workers. However, until mid-1943 it lacked both the numbers of heavy bombers and the technology to guide them to their targets to have a real impact on the German economy. From 5 March 1943, numbers of bombers, plus electronic guidance systems, allowed it to launch relentless attacks on German industry in the "Battle of the Ruhr", which continued for five months with a total of 34,000 tons of bombs dropped, plus daylight harassing raids by light Mosquito bombers. This period included Operation CHASTISE, the famous Dambusters raid on the Moehne and Eder rivers.

Tooze remarks that, "Reading contemporary sources, there can be no doubt that the Battle of the Ruhr marked a turning point in the history of the German war economy, which has been grossly underestimated by post-war accounts." The Ruhr was Europe's most important production centre for coking coal and steel, as well as for intermediate components vital for all sectors of the German war economy. The Battle of the Ruhr provoked Albert Speer to to declare the Ruhr a war zone, with the industrial workforce reorganised on paramilitary lines to allow them to be re-deployed at moment's notice from bomb-damaged factories to operational ones. But this was little more than a damage-limitation exercise: steel production fell by 200,000 tons in mid-1943. On top of pre-existing shortages, this gave the entire German economy a shortfall of 400,000 tons of steel. This in turn required an immediate cut in ammunition production: after more than doubling in 1942, ammunition production in 1943 increased by only 20 per cent. Between July 1943 and March 1944, there was no further increase in monthly aircraft production owing to a critical shortage of intermediate components. Across the whole German armaments industry, from February 1942 to May 1943, it had enjoyed a relatively smooth monthly growth in production of 5.5%. After the Battle of the Ruhr, from May 1943 to February 1944, the average monthly growth rate was 0%.

The RAF and USAAF miscalculated, however, in July 1943 when it turned its attention from the Ruhr to the major Elbe river port of Hamburg, incinerating the city in a firestorm that killed forty thousand people (by comparison, no more than twenty-five thousand would die in the bombing of Dresden) and caused nine hundred thousand more to flee. Albert Speer remarked after the war that had the Allies done that to just three or four other major cities, so many people would have fled into the countryside that the Third Reich would probably have collapsed. However, igniting a firestorm required extremely specific atmospheric conditions and the RAF succeeded in causing one more in 1943, in Kassel on 22 October. It was then distracted in trying to repeat the result in Berlin. While Berlin was a major manufacturing centre in its own right and had obvious political and morale significance as a target, the Ruhr was the chokepoint for the German economy: shutting down its coal and steel production, or severing its links to the rest of the country, had the potential to disrupt the entire industrial economy, and the failure by the RAF to press the attacks on the Ruhr was a serious operational error.

In March 1943 the British and Americans disposed of 1,000 aircraft with a combined bomb weight of 4,000 tons. By February 1944, this had risen to 3,000 bombers, increasing to 5,250 in July 1944, now capable of delivering 20,000 tons of bombs in a single lift. For much of mid 1943 to early 1944, this was committed to Operation Pointblank against the German air industry, aimed at destroying German aircraft production as well as forcing the Luftwaffe into a decisive defensive campaign that would annihilate much of its strength in preparation for the invasion of Europe. From June 1944 it could be turned against German industry as a whole. It had its best effects when it was turned not against German industrial areas (though the sheer devastation inflicted on German cities certainly dented war production), but against transport infrastructure. From September to October, canals, rail yards and bridges into the Ruhr were targeted. In early October one of only fifty ore trains was making it into the Ruhr, and for lack of iron ore, steel production in the Ruhr in January 1945 was down by 66% compared to the previous year. On 11 November 1944, Speer had to report to Hitler that the Ruhr was effectively sealed off from Germany. Coal shortages accounted for production falls of 80% in some factories, while others were forced to close completely. Spring 1945, just before the German surrender, gives the most extreme illustration of the bombing's effect on German industry: dwellers along the Rhine noted that the river was running clean for the first time in generations. There were no factories left in operation to pollute it.

In summary, even in mid-1943 Allied strategic bombing was capable of doing significant damage to the German war effort, as illustrated by the Battle of the Ruhr. However, it was at its most effective when scarce bomber assets were concentrated, not against factories or manufacturing districts themselves, but against the infrastructure to support manufacturing: losses in coal, steel, and intermediate components production caused massive declines in armaments production at a time when the Reich needed every gun, tank and shell it could lay its hands on. The Battle of the Ruhr coincides with the defeat at Kursk, the Allied invasions of Sicily and Italy, and the clear beginning of Germany fighting on the defensive, leading to its ultimate defeat. However, commanders like Arthur Harris were distracted in attacking German industrial areas with the aim of killing or driving away workers to collapse manufacturing, when they lacked the numbers of bombers to cause the sheer devastation needed in a short amount of time to cause the entire country to suffer a moral collapse. It was only by mid 1944, by which time the Soviets were in the middle of Poland and the British and Americans were ashore in Normandy, that the bomber barons had the numbers of planes to attack not just big cities, but also smaller towns that acted as transport hubs needed to support German industry: Allied bombing strategy actually shifted away from prioritising transport targets in November-December 1944, but the sheer number of bombers now committed and weight of bombs dropped was sufficient to bring about near-total collapse. Arguably, though, by this point it didn't matter anymore.