The real problem is that due to his legal problems in 2 American states now, his visa runs a risk of being revoked and his *** deported back to Canada. Then he would be our problem again.
I've been arrested in New York State for going 75mph (!) in a 30 zone and they still accept me, although I'm not a permanent resident to neither Canada or USA. So, I really doubt Bieber will get a ban for his charges.
Homeland Security is not as scary as it's put out to be, from my experience =)