Obama: US has to enforce international norms because UN can't

So is this going to apply to Iran too? Can he at least make it preventative rather than reactive?

“I have no interest in any kind of open-ended conflict in Syria,”
Obama said in an interview with the PBS NewsHour, stressing that he has
not decided to order a military attack.

“But we do have to make
sure that when countries break international norms on chemical weapons
they are held