The radar superiority is not a fact, just a nationalist fantasy in your head.
Cavity Magnetron Tubes were first produced for RAF by the British TUNGSRAM in London. The Hungarian-British corporation was the highest quality (And most expensive) producer of any type of radio tubes (incl. cavity magnetron) in the UK. Hungarians also produced cavity magnetron tubes in Hungarian Tungsram that time. Both Hungarian and British Tungsram firms were the Rolls-Royce of electron tubes in the pre 1945 era.
The British did have the best radar, but they did turn to the American electronics manufacturing to produce large scale radar. The British made the most expensive magnetron, but that is not what you want for combat, you want to mass produce them as cheap as possible and that is where.the Americans in in.
The British also developed the proximity fuses, which the Americans improved upon and manufactured. The proximity fuse gave the Allies a decisive edge in anti-air craft fire, since the anti-aircraft shell would explode when they got near an airplane and did not need to get a direct hit or have to be set to explode at a present height like the Axis, making the Allied anti-aircraft fire more effective.
And it was the American Wright Brothers who built the fist successful airplane and the first wind tunnel, and first effective controls of airplanes, which was fundamental to success aircraft.
And the work of the German rocket scientist was dependent on the earlier work of the American Goddard, who developed the first liquid fuel rockets, the basis for all modern space rockets.
The fact is is that the American fighter planes such as the P51 were superior to the German fighters, being faster and having longer range. The Germans had a lot of interesting ideas, but most never saw combat, and having superior technology available in combat was more important than better technology in prototype.
German Hans Erich (Eric) Hollmann invents the cavity magnetron in 1935 ,filed a patent in 1936 long before the Brits and granted a patent only in 1938 ..
And the entire electronic vacuum tube industry depended on the discovery of Edison of the Edison Effect, and de Forrest making the first practical electronic amplifier. The fact remains the Allied radar was superior to Axis, including German radar. Superior Allied radar gave them decisive edge over Germany and the other Axis countries.
Yes , Randall and Boot improved it significantly and built a advanced version with more than 4 cavities in 1940 but they didn't invent anything ! they simply copied ,worked on and improved an existing technology.
And all the German airplanes could be said to be improvement on the Wright Brothers in the the same way. The principle of using batteries underwater and internal combustion engines on the surface to propel the sub and recharg the batteries was pioneered by Holland in the US, so you could say the German U-boats were mere improvements on the basic design too.
The fact was the Allied radar was better. The Allied (British and later American) succeeded in making effective proximity fuses, something the Germans failed at. I
Americans build atom bomb from the knowledge of an invention of Hungarian E. Teller and German or German educated scientists who left nazi Germany because of political reasons. Americans were taught by European scientists about nuclear physics until the mid 1950s.
It was the Americans who discovered the speed of light was a constant in the Michelson-Morely experiment, an experiment critical to Einstein's theory of relativity. The American Lawrence built the first cyclotron, and received the 1939 Nobel Physics prize, so American was not as completely devoid of physicist as you claim.
And without the production of plutonium, or chemical concentration of uranium, the atomic bomb would not be possible. The construction of the atomic bomb was a truly international effort, the combined effort of scientist from many countries. Enrico Fermi, an Italian, and others were responsible for the world's first nuclear reactor. While.many, most of the scientist that worked on the atomic bomb program were European, many of them were not German, and the thing they had in common was the fascist policies of the Axis countries driving them to the US.
The fact is, despite all the vaunted claims for the Germans, they were inferior in electronics, their radar inferior, and never managed to develop a proximity fuse like the Allies. The planes they put in service for the most part were inferior to the Allied, having no heavy to compare to a Lancaster, or B17 or B29, and no fighter with the range of a P51, and only a few late models German planes late in the war in limited numbers could match its speed. German jets were all very well, but it would have been more helpful to have faster and longer range conventional planes when it mattered, like in the Battle of Britain.