Why have American scientists contributed so much in these decades?

First, you should have enough ability to attract and retain talents. As an immigrant country, American imperialists have been using various resources to attract talents from all over the world.

Second, a better research environment is conducive to scientific development and achievements. Including human environment and equipment, technical support environment. Some countries have not come up with a good solution. Writing a thesis with an evaluation title restricts the development of talents who are really engaged in scientific research and technology, which is almost equivalent to forcing diligent talents to have nowhere to display. Once there are achievements, leaders at all levels will take credit. Such a humanistic environment is definitely not conducive to the development of talents. Equipment and technology often need a lot of money, and the United States has money in this respect, which is much stronger than our country.

Third, the whole market environment. Some people's research is valuable, and sharp businessmen in the market immediately intervene to actively promote the development of science and technology. Even if he is selfish, his technology is objectively progressing.

Fourth, the pressure of survival is small. The pressure on education, medical care, old-age care and housing is much smaller than that of Imperial Capital. You can concentrate more on your major.