It is far too soon to make any judgments about the car bomb that was placed in Times Square Saturday night. It is also too soon to dismiss or accept the Pakistani Taliban’s posted claim of credit for the car bomb—which said the attempted attack was in retaliation for the recent killing of two al Qaeda leaders in Iraq.

From previous experience investigating terrorist attacks (since 1977), I know you need to let the investigation proceed before making any assessment of who may have been responsible for this attempted act of violence. The NYPD and FBI investigators on the scene are the best we have.

That said, we ought to take a look at another plot that was foiled last year to attack the Big Apple for some insights into how our most deadly enemy, al Qaeda, is plotting against us. Last month, Zarein Ahmedzay joined Najibullah Zazi in pleading guilty to a plan to blow themselves up last September—on the eighth anniversary of the 9/11 attacks—on New York subway trains as they passed through Times Square and Grand Central Station at rush hour.

Their guilty pleas reveal that they were working for al Qaeda. Ahmedzay and Zazi are Afghan Americans who went to Peshwar, Pakistan, in August 2008 to join the Taliban and fight the NATO army in their homeland. The Taliban introduced them to two senior al Qaeda officials, who encouraged them to go back to America to carry out terror and not waste themselves in Afghanistan. After bomb training in Waziristan, they agreed.

The senior al Qaeda officials they met with included Rashid Rauf, a British citizen of Pakistani parents born in Birmingham, England. Rauf was the central player in the 2006 al Qaeda plot to blow up simultaneously between seven and 10 jumbo jets en route from the U.K. to Canada and the U.S. on the fifth anniversary of 9/11. The potential suicide bombers have since been convicted in London and we have seen some of their martyrdom videos played at their trials. Their explosives have been tested and we know they would have worked.

Rauf was arrested in Pakistan for the plot; he was the go-between moving back and forth from London to Pakistan to coordinate the attack with al Qaeda’s senior leadership. Rauf escaped from prison in 2007, almost certainly with the help of insiders in the Pakistan intelligence service. He was believed to have been killed in a drone attack in 2008, but British officials told me last week they are not certain of his death.

A third individual is still under indictment in the subway plot and we may learn more if he pleads guilty or goes to trial. What is clear is that al Qaeda has still got the Big Apple in its gun sights. Whether they had anything to do with Saturday’s car bomb or not, we know they are determined to strike inside America again. It is also clear from the Zazi plot and others uncovered in the last six months that al Qaeda has asked all of its allies in the global Islamic jihad, like the Taliban and Lashkar e Tayyiba, and its franchises around the Muslim world, including the one in Yemen, to help it find killers and press the war on America.