About 25% of US Muslims under 30 believe suicide bombings can be sometimes justified.

Only 40% of all US Muslims believe Arab men carried out the 9/11 attacks.

33% of all US Muslims think the invasion of Afghanistan was wrong.

One in four younger U.S. Muslims say suicide bombings to defend their religion are acceptable at least in some circumstances, though most Muslim Americans overwhelmingly reject the tactic and are critical of Islamic extremism and al-Qaida, a poll says.

... U.S. Muslims are far less accepting of suicide attacks than Muslims in many other nations. In surveys Pew conducted last year, support in some Muslim countries exceeded 50 percent, while it was considered justifiable by about one in four Muslims in Britain and Spain, and one in three in France.

Six in 10 said they are concerned about a rise in Islamic extremism in the U.S., while three in four expressed similar worries about extremism around the world.
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One in four consider the U.S. fight against terrorism a sincere attempt to curtail international terror. Only 40 percent said they believe Arab men carried out the attacks of Sept. 11, 2001.

By six to one, they say the U.S. was wrong to invade Iraq, while a third say the same about Afghanistan — far deeper than the opposition expressed by the general U.S. public.