The U.S. has made several overtures in response to the death of 24 Pakistani soldiers possibly from a NATO drone, but while Pakistani officials scold the U.S. for the alleged friendly fire incident, some observers suggest the U.S. respond with a tougher approach.
"We have had soft diplomacy with them for along time, giving them aid with no conditions whatsoever. We've got to stop that," said retired Gen. Jack Keane. "And that's the reality of that -- maintain the relationship and change the conditions of that relationship so that when we provide them support there's conditions that go along with that, and we want certain things back for that."
"I would tie whatever aid money we are giving to Pakistan, if they deserve any at all -- to access (the) drone base, keeping the supply lines open, working rigorously with us on counter terrorism," said Republican presidential candidate Jon Huntsman.
Secretary of State Hillary Clinton and Defense Secretary Leon Panetta have offered their condolences over the deaths, which Afghan officials say was the result of a request for NATO backup following an attack on Afghan troops from the Pakistan border region.
Other senior officials have also been in contact with Pakistani officials, said National Security Council spokesman Tommy Vietor.
"Senior U.S. civilian and military officials have been in touch with their Pakistani counterparts from Islamabad, Kabul and Washington to express our condolences, our desire to work together to determine what took place, and our commitment to the U.S.-Pakistan partnership which advances our shared interests, including fighting terrorism in the region," Vietor said.
NATO and U.S. forces are now investigating the incident, which led to Pakistan ordering the allies to vacate an air base that has been used as a backup installation when nasty weather prevents the drones from returning to bases in Afghanistan.
Nonetheless, Pakistani Foreign Minister Hina Rabbani Khar told Clinton on Sunday that the alleged NATO attack negated all progress in improving the damaged alliance between the two countries. The Pakistani foreign minister's office said Khar told Clinton in a phone call that the alleged NATO attack was unacceptable, showed complete disregard for human life and sparked rage within Pakistan.
But the new trough -- following Pakistan's anger at U.S. silence before its raid on the compound where Usama bin Laden was found -- may not be lasting.
Aside from the fact the allies are less reliant on Pakistan because they have reduced shipments of non-lethal supplies from there into Afghanistan, Sen. Jon Kyl, R-Ariz., said the Pakistanis are dependent on billions in U.S. aid dollars.
"There's a lot of diplomacy that has to occur and it has to be tough diplomacy in the sense that they need to understand that our support for them financially is dependent on their cooperation with us. But it's not the kind of situation where you just cut off all assistance because we do need their (location) in the region," Kyl said.
Charles "Cully" Stimson, a former assistant defense secretary for detainees, said military-to-military relations remain "quite good" but an appeasement between the two nations will require presidential leadership. President Obama needs to "personally appeal" to Pakistan's leaders, he said, to help "cool things down."
Stimson added that a bigger concern for the U.S. is making sure relations don't tip off the deep end.
"There are nukes in Pakistan," he said. "They move them in unconventional ways, from one place to the next. And if those nukes got in the hands of the Haqqani Network or the Taliban or al Qaeda, that would be a disaster so we can't let that happen."
Former U.S. ambassador to the U.N. John Bolton agreed that relations must be kept positive.
"It's tempting for people to say we ought to just throw the Pakistanis over the side and stop giving them the aid and all the rest of it," he said. "As long as that country has nuclear weapons that could fall into the hands of radicals and be a threat worldwide, they've got incredible leverage."
With anger simmering -- thousands protested Sunday outside the U.S. consulate in Karachi -- the Pakistanis have closed two border crossing points between Afghanistan and Pakistan -- Torkham in the northwest Khyber tribal area and Chaman in southwestern Baluchistan province.
That means ground lines with Pakistan are closed and remaining supply routes are blocked.
Brigadier Gen. Carsten Jacobsen, a spokesman for the International Security Assistance Force, told Fox News the cross-border area was dangerous to begin with, but now an inability to communicate "only serves one side and that is the insurgency."
"This is exactly the area where ... terrorists are operating on either side of the border, they use it for safe haven, use it for migrating across the border, use it for firing at us as well at the Pakistani forces. So it's a very vile area, very dangerous," he said.
Sen. Dick Durbin, the No. 2 Democrat in the Senate, said that while he is saddened by the deaths, the latest incident demonstrates another example of why the U.S. should abandon the region.
"As difficult as it is to find our way through this diplomatic morass between the incompetence and maybe corruption in Afghanistan and the complicity in parts of Pakistan, our soldiers are caught right in the middle of this," he said. "At a time when they're trying to bring peace to this region, I think it's an argument, from my point of view, of moving us toward the day when our American soldiers come home."
The Associated Press contributed to this report.