Re: Because the US is well known for respecting other countries' courts
While .com is controlled by Verisign, a U.S company, there are registrars operating in various jurisdictions giving out .com domain names under contract with Verisign. Any jurisdiction with such a registrar could order them to transfer a domain to that government. Indeed, Verisign it's self has offices outside the U.S.
A seizure would have to be the topic fairly serious contention for either the U.S government or Verisign to get involved. The domain most governments would want seize are probably a long way from that level.