They weren't when I was in the hard sciences back in the 70's. Back then, the main influx was a lot of Indians and Pakistanis (before China). They got preferred treatment (grants, scholarships and school jobs) and got free rides while we had to work our butts off at Summer jobs etc. to stay in school and avoid the student-loan trap. They often could not speak an intelligible form of english, and they were often not any brighter or harder working than many of my classmates at the University of Minnesota. Some of these graduate Teaching Assts. could not even fathom the undergraduate lesson plans. (I am speaking of Physics, Chemistry, Math, and as they called it then, Computer Science). They were a measurable impediment to the average student in their classes. But PC, even then, prohibited any direct action to cure the problem, and grumbling in the classroom was effectively neutralized, as the U.S. displacement machine ground on.
I think it fair to say, a healthy proportion of my classmates assumed these folks were being given PC grade inflation.
I also noticed that many of them seemed to gravitate into nuclear phsyics and wanted to learn how to enrich uranium, and build atom bombs.
I doubt this is correct. The reason universities like foreign students is because they are generally a cash cow for the school. Unless one is a permanent resident, they do not qualify for government-backed scholarships, grants and loans. So, these students from Pakistan and India were probably either paying their own way or they received scholarships from their own governments.
Well when I went to University in the US just a few years ago I noticed that especially Indians were much brighter than the American students. I as a Norwegian was an average student in math. Another interesting fact that you wrote was that they barely knew the language. That means that they have to work harder and be smarter to get the same scores, but they did better. I know since I studyed in the US and know how language barriers makes thing harder. Since I am from Europe it is not that big a deal, but for other people from China it must be very hard.
I was in engineering school in the late 80s and early 90s, and it was pretty much understood that the school accepted so many foreigners simply because they didn't get "free rides" -- their governments paid most of their costs.
No cheers, unfortunately.