Ask A Historian

[Minimalist]

I think you mean the B-17 Wyrd.  The B-29 program dates to 1938 and, as a precision high-level bomber it was something of a flop.

As I said, the US did fund the B29 as the primary weapons system to be used against Japan before the war started.  Germany & Japan did not have a similar bomber.  They thought that they were fighting a war like WWI.  The B29 was very effective against Japan, which was its purpose.

That's not what the Office of Air Force History says:

https://en.wikipedia.org/wiki/Boeing_B-2...v5p11-2-41

Boeing began work on pressurized long-range bombers in 1938, in response to a United States Army Air Corps request. Boeing's design study for the Model 334 was a pressurized derivative of the Boeing B-17 Flying Fortress with nosewheel undercarriage. Although the Air Corps did not have money to pursue the design, Boeing continued development with its own funds as a private venture.[4] In April 1939, Charles Lindbergh convinced general Henry H. Arnold to produce a new bomber in large numbers to counter the Nazi production.[5] The Air Corps issued a formal specification for a so-called "superbomber", capable of delivering 20,000 lb (9,100 kg) of bombs to a target 2,667 mi (4,290 km) away and capable of flying at a speed of 400 mph (640 km/h) in December 1939. Boeing's previous private venture studies formed the starting point for its response to this specification.[/url]

And then,

In September 1941, the Army Air Forces plans for war against Germany and Japan proposed basing the B-29 in Egypt for operations against Germany as British airbases were likely to be overcrowded.[url=https://en.wikipedia.org/wiki/Boeing_B-29_Superfortress#cite_note-AAFWW2_v1p145-9-39][35][36] Air Force planning throughout 1942 and early 1943 continued to have the B-29 deployed initially against Germany, only transferring to the Pacific after the end of the war in Europe. By the end of 1943, however, plans had changed, partly due to production delays, and the B-29 was dedicated to the Pacific Theater.

When it was transferred it was a mainly morale-building exercise for China as some B-29s were based in China.  There were no Pacific bases within range of Japan until the Marianas were taken in mid 1944 and even then bases had to be developed for the B-29s to be launched.

Finally, general LeMay in command of the B-29s determined, for a number of reasons, that high-altitude, daylight, "precision" strikes against Japan (what the B-29 was specifically designed to do) were  and would continue to be ineffective against Japan.  His solution was low-level, nighttime, incendiary raids, which were highly effective and, frankly, more deadly than the atomic bomb strikes. 

By the time this tactic was worked (March-1945) out the Japanese navy had virtually ceased to exist and the army in China and the Philippines was thus effectively isolated from the homeland by allied subs and marauding carrier groups.  The shortages of food and fuel and raw materials would have condemned the civil population to extreme hardship in the winter of 1945/46 if Japan had not surrendered.  The war was decided militarily long before the B-29s began to make any meaningful impact.  In fact, Tokyo had begun putting out peace feelers through neutrals ( including the fucking pope!) in January of 1945.  This is not to say that there were not firebrands ready to fight to the death but the government understood that they had lost the war with the battles of the Philippine Sea and Leyte Gulf.