Specifically on devaluing the currency: this doesn't really work like people imagine it would since the US continually turns over its debt by paying older bonds

Specifically on devaluing the currency: this doesn't really work like people imagine it would since the US continually turns over its debt by paying older bonds and issuing new ones. If it started to look like the US was devaluing its currency we'd quickly find ourselves unable to issue new bonds, and it basically turns into the mother of all margin calls.