

I was wrong on one thing - he was in Hong Kong, yes, but he was already boarding his flight when it was revoked.
On June 14, the U.S. Justice Department filed criminal charges against Snowden in federal district court.3 The following day, the Justice Department formally requested that Hong Kong authorities issue a provisional arrest warrant for Snowden.4 Eight days later, on the very morning—Hong Kong time—that his passport was revoked, Mr. Snowden was able to board a flight to Moscow.
https://yalelawjournal.org/essay/citizenship-passports-and-the-legal-identity-of-americans
Here’s the official statement from Hong Kong
https://www.info.gov.hk/gia/general/201306/23/P201306230476.htm
Mr Edward Snowden left Hong Kong today (June 23) on his own accord for a third country through a lawful and normal channel.
The US Government earlier on made a request to the HKSAR Government for the issue of a provisional warrant of arrest against Mr Snowden. Since the documents provided by the US Government did not fully comply with the legal requirements under Hong Kong law, the HKSAR Government has requested the US Government to provide additional information so that the Department of Justice could consider whether the US Government’s request can meet the relevant legal conditions. As the HKSAR Government has yet to have sufficient information to process the request for provisional warrant of arrest, there is no legal basis to restrict Mr Snowden from leaving Hong Kong.
And before people say China collusion, this is 2013, when HK was still autonomous.
No, belief is not required. Again, see example of Jewish secular.