The answer is easy. Power America has always been wary of educated masses. They see Europe and its unemployed educated masses striking for more benefits and social changes and would rather keep America a content, middle "working" class, blue collar workforce.
America brain drained the world after WW2, taking in STEM expertise from winner and loser countries. America represented the land of opportunity and many chose expatriation to start a new life.
Twenty years later local stem talent simply wasn't enough to fill the available jobs and universities started marketing themselves to the world. That was a paradigm shift that caught the rest of world flat footed. Their universities were all state owned and managed, there was no marketing budget to compete. UCLA, Harvard, MIT, etc. became global brands, standards of excellence, justified or not. The brain drain of foreign nationals increased, skimming from developing nations their best and brightest, taking precious educational resources leaving to get their stem PhD in glowing America which didn't have to spend a dime on their education until it really mattered.
The Silicon Valley couldn't have been without foreign talents and certainly couldn't have become the tech powerhouse it has become without all the Indian, Chinese and Eastern European stem PhDs that fill their research centers and tech firms. All these people cost a fraction of the cost of educating Americans with the hope of branching into stem and be competitive with science driven nations.
