"Pakistani governments have come and gone, but it's northwestern frontier has remained a terrorist haven, with its security services supporting what it considers to be good Islamist terrorist groups," Congressman Ed Royce, Chairman of the House Foreign Affairs Committee, said in one of the sharpest attack on Pakistan.
"These good groups, under Pakistan's calculus, destabilise Afghanistan and threaten neighbouring India, while the government simultaneously opposes what it considers the bad Islamist groups," he said.
Chairing a Congressional hearing on Pakistan, Mr Royce said after more than a decade under sanctions for its nuclear proliferation, Pakistan was to be a key ally in combating Islamist terrorism, becoming a leading recipient of US aid in the nearly 15 years of war on terror.
"But while the US was quick to embrace Pakistan, Pakistan has hardly reciprocated," Mr Royce said as he was joined by other top American lawmakers in lashing out at Pakistan.
"The committee has repeatedly urged Pakistan to take meaningful action against key Islamist terrorist groups operating within its territory. Unfortunately, Pakistan, which is now home to the world's fastest growing nuclear weapons program, has remained a fount of radical Islamist thought," he said.
Mr Royce further observed that it was no surprise that one of the San Bernardino attackers, Tashfeen Malik, studied at a Pakistani school spreading a particularly fundamentalist message.
As many as 14 people were killed and 22 injured in a terror attack on December 2, when Malik, along with her Pak-origin husband Syed Rizwan Farook opened firing at a public health training event in San Bernardino.
Looking back, Congressman Ted Poe said, the 9/11 terror attacks transformed US-Pakistan relations overnight. The US has given Pakistan USD 30 billion since 9/11, Mr Poe said.
"I think Pakistan is a Benedict Arnold ally to the US.
Even going back to May 2, 2011, when there was the raid in Pakistan on Osama bin Laden, we didn't tell the Pakistanis we were coming, because, frankly, they would snitch us off and Osama bin Laden would have left," he said.
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