TRIPOLI, Libya - Muammar Gaddafi vowed a "long war" as allied forces launched a second night of strikes on Libya, and jubilant rebels who only a day before were in danger of being crushed by his forces now boasted they would bring him down. The U.S. military said the international assault would hit any Gaddafi forces on the ground that are attacking the opposition.
In an attack that carried as much symbolism as military effect, late Sunday a cruise missile blasted a building in Gaddafi's residential compound, near his iconic tent. It was not known where Gaddafi was at the time, but it seemed to show that while the allies trade nuances over whether his fall is a goal of their campaign -- he is not safe.
An Associated Press photographer escorted to the scene by the Libyan government said half of the round, three-story administration building was knocked down, smoke was rising from it and pieces of the missile were scattered around the scene. About 300 Gaddafi supporters were in the compound at the time. It was not known if any were hurt.
The U.S. military said the bombardment so far -- a rain of Tomahawk cruise missiles and precision bombs from American and European aircraft, including long-range stealth B-2 bombers -- had succeeded in heavily degrading Gaddafi's air defenses.
In addition to targeting anti-aircaft sites, U.S., British and French planes blasted a line of tanks that had been moving on the rebel capital Benghazi, in the opposition-held eastern half of the country. On Sunday, at least seven demolished tanks smoldered in a field 12 miles (20 kilometers) south of Benghazi, many of them with their turrets and treads blown off, alongside charred armored personnel carriers, jeeps and SUVs of the kind used by Gaddafi fighters.
"I feel like in two days max we will destroy Gaddafi," said Ezzeldin Helwani, 35, a rebel standing next to the smoldering wreckage of an armored personnel carrier, the air thick with smoke and the pungent smell of burning rubber. In a grisly sort of battle trophy, celebrating fighters hung a severed goat's head with a cigarette in its mouth from the turret of one of the gutted tanks.
The strikes that began early Sunday gave immediate, if temporary, relief to Benghazi, which the day before had been under a heavy attack that killed at least 120 people. The city's calm on Sunday highlighted the dramatic turnaround that the allied strikes bring to Libya's month-old upheaval: For the past 10 days, Gaddafi's forces had been on a triumphant offensive against the rebel-held east, driving opposition fighters back with the overwhelming firepower of tanks, artillery, warplanes and warships.
Now Gaddafi's forces are potential targets for U.S. and European strikes. The U.N. resolution authorizing international military action in Libya not only sets up a no-fly zone but allows "all necessary measures" to prevent attacks on civilians.
But the U.S. military, for the time being at the lead of the international campaign, is trying to walk a fine line over the end game of the assault. It is avoiding for now any appearance that it aims to take out Gaddafi or help the rebels oust him, instead limiting its stated goals to protecting civilians.
At the Pentagon, Navy Vice Adm. William E. Gortney underlined that strikes are not specifically targeting the Libyan leader or his residence in Tripoli. He said that any of Gaddafi's ground forces advancing on the rebels were open targets.
"If they are moving on opposition forces ... yes, we will take them under attack," he told reporters.
"We judge these strikes to have been very effective in significantly degrading the regime's air defense capability," Gortney said. "We believe his forces are under significant stress and suffering from both isolation and a good deal of confusion."
A military official said Air Force B-2 stealth bombers flew 25 hours in a round trip from Whiteman Air Force Base in Missouri and dropped 45 2,000-pound bombs.
What happens if rebel forces eventually go on the offensive against Gaddafi's troops remains unclear. Gortney would not say whether strikes would hit Libyan troops fighting back against rebel assaults.
U.S. Defense Secretary Robert Gates said late Sunday that the U.S. expects turn over control of the operation to a coalition headed by France, Britain or NATO "in a matter of days," reflecting concern that the U.S. military was stretched thin by its current missions. Turkey was blocking NATO action, which requires agreement by all 28 members of the alliance.