Reacting to the Boston Marathon bombings, the chairman of the Joint Chiefs of Staff on Tuesday charged that there is a "global effort" to whip up and recruit young American Muslims over the Internet, including those responsible for the Patriots' Day attack.

Army Gen. Martin E. Dempsey also said that if the two Russian-born men tied to the bombing were part of a broader Chechnya-based terror network, then the U.S. government will have to focus on the violent separatist region.

"I think that Chechnya has been a concern for some time actually, it certainly has been for the Russians," Dempsey said at a D.C. media luncheon hosted by the Christian Science Monitor.

"If this is an indication, if -- this is a big if -- if this is an indication of them exporting that to the U.S., then certainly we would have to do the analysis to better understand it better than we probably have," said America's top general.

But if it turns out to be homegrown terrorism, he added, then efforts to combat global terrorism activity aimed at the U.S. need to be beefed up to encompass "the insider threat that could occur over time because of self-radicalization over the Internet."

That, he said, is a real concern. "There is this global effort to take some of our more vulnerable, notably Muslim, young men and women, in a direction counter to our values, and it bears increased interest it seems to me in the aftermath of the Boston tragedy."