WASHINGTON -- In Miami last month, and now in New York, terrorism cases have unfolded in which suspects have been apprehended before they lined up the intended weapons and the necessary financing or figured out other central details necessary to carry out their plots.
For officials in Washington, it is a demonstration of the much-needed emphasis in this post-Sept. 11 era for pre-emptive arrests.
"We don't wait until someone has lit the fuse to step in," Homeland Security Secretary Michael Chertoff said Friday at a news conference about the New York plot.
But the Miami and New York cases are inspiring a new round of skepticism from some lawyers who are openly questioning whether the government, in its zeal to stop terrorism, is forgetting an element central to any case: intent to commit a crime.
"Talk without any kind of an action means nothing," said Martin R. Stolar, a New York defense lawyer. "You start to criminalize people who are not really criminals."
In the two most recent suspected plots, the authorities have simultaneously warned that the suspects were contemplating horrific attacks - blowing up the Sears Tower in Chicago and setting off a bomb in a tunnel between New York and New Jersey - but then added that as far as they knew, no one was close to making such a strike.
In the Miami case, an FBI official said at a recent hearing that the suspects apparently did not have written information on how to make explosives, details on the Sears Tower layout or a known link to a terrorist group.
In New York, officials said Friday that none of the eight suspects believed to be planning the tunnel attack were in the United States, that they apparently did not have bomb materials and that they had not completed reconnaissance on their supposed target.
The arrest April 27 in Beirut, Lebanon, of Assem Hammoud, 31, a Lebanese man who is accused of being the mastermind of the tunnel plot, came after the authorities monitored Internet chat rooms used by Islamic extremists who had used coded language to discuss a possible attack. One U.S. official said the members of the group had never met one another.
In announcing the case, federal officials, including Chertoff, said the government could not waste time trying to determine whether the suspects were smart enough or serious enough to turn their threats into destructive action.
"It is a mistake to assume that the only terrorist that's a serious terrorist is the kind of guy you see on television, that's a kind of James Bond type," Chertoff said Friday. "The fact of the matter is, mixing a bomb in a bathtub does not take rocket science."
Rep. Peter T. King, a New York Republican who leads the House Committee on Homeland Security, said the cases also demonstrate that the authorities cannot always delay charges until they have built airtight criminal cases.
"It was essential that the FBI get rid of its pre-9/11 mentality of not making an arrest until they have enough evidence to convict," King said Friday. "You can't be locking everyone up. But so long as there are reasonable grounds to make the arrest, they should do that."
Mark J. Mershon, an FBI assistant director, said that the apprehensions related to the New York case - no one has been arrested in the United States - began after the authorities were convinced that the talk was close to turning into action.
"Plotting for this attack had matured to a point where it appeared that the individuals were about to move forward," Mershon said Friday in New York. "They were about to go to a phase where they would attempt to surveil targets, establish a regimen of attack and acquire the resources necessary to effectuate the attacks."
Carl W. Tobias, a University of Richmond law professor who tracks terrorism cases, said the modest evidence disclosed in some recent cases related to the ability of the suspects to deliver on their threats has caused him to wonder if politics might be a factor. "There is some kind of public relations gained by making Americans on the one hand feel concerned that the Sears Tower in Chicago or some tunnel in Manhattan is targeted, yet on the other hand feel comforted that the government is on top of it," he said.
Questions posed about some of the terrorism-related arrests echo doubts raised when Tom Ridge was secretary of the Homeland Security Department and the Bush administration a half-dozen times raised the color-coded alert warning to orange from yellow, signaling a heightened risk of a terrorist attack, leading skeptics to suggest that the up-and-down warning levels might have been driven in part by politics.
Since the Sept. 11 attacks, according to a Justice Department tally, 261 defendants have been convicted or have pleaded guilty in terrorism or terrorism-related cases. But many of those cases have only remote connections to actual terrorism plots, such as the case involving six men from Lackawanna, N.Y., who pleaded guilty to attending a terrorist training camp but never took part in a terror plot.