Diao Daming is certainly right that U.S. (and Western) “China studies” is moving away from fieldwork and lived experience, with negative consequences for understanding; factors both from the U.S. and China: (increasing anti-China sentiment) and restrictions on the China side; However, there is no blanket ban on Americans visiting and researching in China—on recent trips to China I’ve been told by Chinese colleagues how hard they are trying to get foreign scholars to come visit, but its very hard to get Americans—more Europeans but still fewer than before. There are quotas to recruit a certain number of foreign scholars at certain universities. But the question of what you can actually research in China is crucial to this—archives are harder to access, forget about interviewing most government officials at least in any public or official capacity; some topics are easier, if they are non-political , daily life, and not interviewing officials or elites; but anyone in the public sector is extremely wary of interacting with foreigners, mostly because they’re afraid of getting in trouble.