Maybe. But they still can’t search backpacks. So even if there is no terrorism link here (and they always seem to say that these days) what’s to prevent there from being one next time? From AP, :
A backpack that set off a small explosion in a Times Square subway station may have contained a pipe bomb and not just fireworks, as originally believed, police said Tuesday.
The explosion at 8 p.m. Monday slightly injured a retired police officer and disrupted subway service.
Scores of heavily armed police trained in anti-terrorism tactics and hundreds of other officers sealed off parts of the surrounding streets around 43rd Street and Eighth Avenue.
Investigators said later, however, that they did not suspect any terrorism link.