@dassauerkraut @faithisleaping Math Ph.D.s in the US - along with most other Ph.D.s - are handed out to people as long as they meet three criteria:
1) They are not intellectually a threat to their advisor.
2) They adhere to the status quo ideologically.
3) They stick around the program for long enough.

Ph.D.s gotten from US institutions within the last 15 years should be viewed as certificates that an individual is not likely to come up with something novel and lacks independent thought.