The US regularly seize domains, even those with foreign registrars. I don’t feel that any tld is immune from this. Sure there are some TLDs more at risk than others, like .af being in control of the Taliban, but I’d also say US controlled TLDs are not the least at risk.

Some interesting articles about this

securityweek.com/country-specific-web-domains-can…

en.m.wikipedia.org/wiki/Operation_In_Our_Sites

www.wired.com/2012/03/feds-seize-foreign-sites/