US Muslims more peaceful than their fellow citizens?

The interweb is all atwitter over some of the findings of a Pew Research Center study of the attitudes of Muslim-Americans (the most comprehensive one done yet). While most of the findings should be welcomed (US Muslims are well off, appreciate being here, have non-Muslim friends, shun extremism, etc.), there is one troubling statistic: 6% of US Muslims - and 15% of US Muslims under 30 - believe that "bombing and other attacks intentionally aimed at civilians" are "often or sometimes justified". Sounds bad, but what happens when you ask the same question of non-Muslim Americans? Turns out that 24% of all Americans agreed - four times the 6% of US Muslims who share that view. So are US Muslims more peaceful than their non-Muslim neighbors?