Two members of an alleged bomb-making operation with links to Al Qaeda, including a New York imam, were ordered held without bail Monday.
It is a crucial question in terrorism cases: When should the government step in and make arrests?
If US law enforcement waits for bombs to be made, it may act too late, and innocent people could be hurt. If it acts too soon, it may not have an airtight case, or maybe any case at all.
In its latest terror arrests, involving three men born in Afghanistan, the government seems to have decided it was riskier to not act, say some terrorism experts. After all, the UN General Assembly is preparing to meet in New York this week, followed by the Group of 20 summit in Pittsburgh. Any terror incident would instantly gain world attention.
In fact, one of the defendants was on his way to New York just before Sept. 11.
"The critical issue is, when should the government intervene and intercept?" says Carl Tobias, a law professor at the University of Richmond in Virginia who follows terror investigations. "In all cases, it's a different calculus."
For example, in May of this year, the New York Police Department arrested four men – three of them Muslim converts, according to the Associated Press – as they allegedly tried to plant a bomb at a synagogue in the Bronx. The supposed bomb was actually an FBI-altered device, and the men's defense attorneys are claiming entrapment. The case is pending.