Are you a U.S. citizen? If not, when you choose to commit crimes while you're a guest in another country, then choose to become a fugitive instead of taking responsibility for your actions, you send a pretty clear message to that country that you're an undesirable person. If a warrant shows up in a USCIS check at a port of entry, even if they don't detain you for prosecution, they can tell you to turn around and go home.