The normally skeptical and even-keeled Peter Bergen thinks something strange is going on. The breakup of a seven-man domestic terror cell in North Carolina has the author of Holy War, Inc worried that America is becoming a seat of homegrown terrorism. As he told radio interviewers this morning, most terror cases since 9/11 were more about talk than action.

But now, he said, "we've seen a lot of cases in the last year or so where I think the bar is higher."

He goes on to list a spate of recent domestic terror suspects who traveled overseas for training and radicalization-- including a Somali American from Minnesota who committed the first known suicide attack by an American citizen, and similar incidents by men from Arkansas and Long Island.

Now, the North Carolina case has him worried because one of the suspects recently traveled to Pakistan, and others may have gone scouting for terror opportunities in Kosovo and Israel.

So is there a pattern of homegrown, all-American jihadists emerging? Even the staunch Bergen can't say "no."

"There is a sort of mini-wavelet right now. Does it make a constellation? I'm not sure. Does it make something of a pattern? Perhaps. Because American Muslims tend to be better educated, have higher incomes...I and others thought we would be insulated from this phenomenon. But when you have several cases like these popping up in the same year, you have to ask yourself the question: Is that really the case? Is there the possibility of a homegrown radical movement in the United States? These four cases we've discussed may amount to more than just isolated incidents."

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