In Iran, several political and military leaders have announced that the Revolutionary Guard Corps has recruited some 50,000 "volunteers for martyrdom," men and women pledged to use suicide tactics if the country is attacked. During a very large recent military exercise that involved elements of the regular armed forces, Revolutionary Guard, and national militia, upwards of a thousand suicide commandos reportedly took part. While there may actually be 50,000 volunteers for suicide missions, it's likely that the actually number of people who have been given any training is less than 10-percent of that.
Iran has not been exporting terrorists, and has been rather careful to avoid doing anything that could be traced back to Iran or the Iranian government. Thus the biggest danger to the United States is believed to be capable freelancers. Individual Arabs or Pakistanis are often on the counter-terrorist most wanted list. For example, a fellow by the name of Yousef Aqel is a Moslem radical on the lam in the Caribbean. Reportedly he's offering big bucks for the capture of, or head of, U.S. military personnel. Most of these bad guys turn out to be boastful stories that got out of control. But occasionally they lead to a real person, who posed a real danger.
Operators like Aqel are interesting because they appear to have financial backers, and a local support network. Then again, police believe Aqel is a gangster who shot his mouth off on the wrong subject. There are many more Aqels in Europe, where young Moslem males often outdo each other in homicidal rants about the horrific terrorist acts they are going to commit. These braggarts drive the cops nuts, trying to figure out which of these angry-young-men are going to actually commit mass murder. The key clue appears to be the presence of a bomb maker and an organizer who can plan an attack well enough to work. So what the cops are really doing is trying to figure out who the bomb makers and planners are. Everyone else is just noise.