Updated 11:06 a.m. ET
The United States has not spoken of providing military support to Libya's rebels, but the U.S. government is making contingency plans, including sending additional ships to the Mediterranean.
CBS News national security correspondent David Martin said there is very little enthusiasm at the Pentagon for entering Libya. "Basically, it threatens getting in the middle of a civil war," Martin said. "But at the same time, they realize they cannot stand by and watch Qaddafi kill civilians."
"We have joined the Libyan people in demanding that Qaddafi must go - now -- without further violence or delay," Secretary of State Hillary Clinton said Tuesday in testimony before the House Committee on Foreign Affairs. "We are taking no options off the table so long as the Libyan government continues to turn its guns on the Libyan people."
Clinton was before the committee to detail the State Department's fiscal 2011 budget request, but also answered numerous questions from committee members, most of them focusing on the turmoil in the Middle East.
Pro-Qaddafi forces tried to retake two cities Monday, but opposition forces in Zawiya and Misrata repelled the attempts. The rebels include mutinous army forces, and are armed with tanks, machine guns and anti-aircraft guns. Meanwhile in the eastern section of the country, CBS News correspondent Mandy Clark reports that government planes bombed a weapons depot.
Martin said that the U.S. already had one guided missile destroyer in the Mediterranean and has now sent a second one.
But before bigger ships can get there, they have to pass through the Suez Canal.
A three-ship amphibious task force with helicopters and 400 Marines on board is now steaming toward the entrance to the canal, said Martin. An aircraft carrier, the Enterprise, along with a cruiser, is already at the entrance waiting for orders to go through.
Martin says the Pentagon is looking at three basic options:
"First, jam Libya's communications so that Qaddafi has a hard time communicating with his forces," he told "Early Show" anchor Chris Wragge. "Second, send those Marines ashore to set up aid stations for the rebel areas. And third, establish a no-fly shown so that Qaddafi cannot use his air force against his own people."
One thing that is not an option for the Pentagon: The U.S. taking on the situation by itself.
"The U.S. does not want to go to it alone here," said Martin. "The famous 'Pottery Barn rules' apply here: You break it, you own it. And if there is chaos in Libya, the U.S. does not want to be the one country responsible for restoring order."
Sanctions against Qaddafi's government have been enacted to squeeze them financially and to cut off the flow of arms to the regime. U.S. Ambassador to the United Nations Susan Rice said on "The Early Show" this morning that Qaddafi must be shown that "the international community is not going to tolerate the slaughter of innocents.
"So we are continuing contingency planning with NATO allies and others for all sorts of options that may be necessary."
"There could be a real humanitarian disaster in Libya as this situation unfolds," Rice told "Early Show" anchor Erica Hill. "And if that is to occur, we and others in the international community would want to be prepared to respond if necessary, promptly and effectively."