York on Monday night , two days after he allegedly attempted to set off a car bomb in Times Square . The bomb failed to detonate . It was the second case in the past six months of a bungled terrorist attack in the United States , following the failed bombing of a U.S. airliner on Christmas Day . Brennan said U.S. counterterrorism efforts had degraded the ability of groups such as al Qaeda and the Taliban to launch successful attacks . `` They 're trying to find vulnerabilities in our defenses , '' Brennan said , noting the attempts have been `` unsophisticated . '' Shahzad , a Pakistani-American , had traveled to Pakistan several times in recent years , Brennan said . `` He was captured by the murderous rhetoric of al Qaeda and TTP , '' Brennan said of the suspect . Preventing attacks by individuals , especially American citizens such as Shahzad , is a `` very difficult challenge , '' Brennan said . The case raised new questions about whether terrorism suspects should be read the Miranda warning that advises them of their rights to remain silent and obtain legal representation . Critics have accused
Washington -LRB- CNN -RRB- -- The man charged in the failed Times Square bombing was working with the Taliban movement in Pakistan , the U.S. attorney general said Sunday . `` The evidence that we have now developed shows the Pakistani Taliban directed this plot , '' Attorney General Eric Holder said , describing the investigation into suspect Faisal Shahzad during an appearance on NBC 's `` Meet the Press . '' `` We know that they helped facilitate it , we know they helped direct it , and I suspect we 're going to come up with evidence that shows they helped to finance it , '' Holder said . John Brennan , the assistant to the president for counterterrorism and homeland security , told CNN 's `` State of the Union '' that the Pakistani Taliban -- also known as Tehrik-e-Taliban , or TTP -- is closely allied with al Qaeda . The group has pledged to carry out attacks outside of central Asia , including the United States , Brennan said Sunday . Shahzad has been charged in the May 1 attempted bombing in Times Square . He was arrested while trying to fly out of New