In a tough, emotional speech marking the 11th anniversary of the revolution that brought him to power, Libya's Col. Muammar Qaddafi tonight demanded an immediate and total union with Syria to step up the Arab confrontation with Israel.

Speaking before an excited, chanting crowd of some 50,000 supporters, Qaddafi -- his hands waving in the air for emphasis -- said that if Syria did not agree to this union, he would leave Libya to join the Palestinian guerrillas to fight Israel on its borders.

"If this union is not accepted immediately, I declare myself, Muammar Qaddafi, a member of the Fedayeen [the Palestinian resistance], and will go join them to fight Israel," Qaddafi said. "I am going to fight and die in Galilee."

The speech was broadcast live on Syrian television, a rare event that led observers here to believe that the Syrian government had prior information about Qaddafi's intent.

The mercurial Qaddafi has a reputation abroad for impulsive rhetroic, and he has frequently called for all-out war against Israel.

Qaddafi's proposal for a union with Syria was made with the Syrian prime minister Abdul Raut Qasim, looking on. Qasim and Syrian Information Minister Ahmed Iskandar Ahmed headed the Syrian delegation to the Libyan ceremonies.

There was no immediate reaction from the Syrians about Qaddafi's proposal.

The history of Arab unions in the Middle East has hardly been encouraging. Syria joined Egypt and Iraq in a short-lived union in the 1960s. Libya twice has proposed unions with Egypt and Tunisia. The first union was as short-lived as Egypt's with Syria, and the second never got off the ground.

Arab officials here said that Qaddafi's offer was a strong gesture of support for Syria, which Qaddafi called "the last trench" on the Israeli front. Non-Libyan Arabs here, however, remained skeptical of the feasibility of the union proposed tonight, given the two countries' different political systems and their geographical separation.

Qaddafi, who earlier in the day had reviewed tens of thousands of troops and armed civilians parading through the streets of Tripoli, also strongly attacked Egyptian President Anwar Sadat, whom he accused of having gone over to the "enemy" -- that is, Israel and the United States. He said Sadat had brought the Israeli front lines to Libya's borders.

Qaddafi said his forces were strong enough to destroy Egypt, but that he would not order them to do so because Egypt was an Arab land.

Early in his often rambling, two-hour-and-fifty-minute speech, Qaddafi said he was parading his country's vast armed manpower instead of his weaponry in the streets this year to put an end to accusations that Libya did not have the trained manpower to use the sophisticated weapons that the country's oil millions have purchased in the last decade.

"We are on the front lines of the struggle against Israel and the United States today, and this is why we have marched so many people through the streets today," he said. "They [Libya's enemies] say we have arms without the people to man them. What you have seen today should prove that Libya has the men to use them, too."

Unlike previous Revolution Day parades -- during which Libya's arsenal of Soviet-supplied tanks, ground-to-ground missiles, and artillary and armored cars were driven through the streets -- this year Libya concentrated on displaying its manpower.

For nearly three hours this morning in an earlier parade, tens of thousands of soldiers, sailors, Air Force personnel, militias, commandos, cadets, and armed student and womens' groups marched before Qaddafi and visiting delegations that sat in canopied reviewing stands against the 16th-century walls of the Spanish fort that sits next to the Green Square, Tripoli's principal plaza.

Although the crowds who watched that parade were sparse -- numbering only around 8,000 -- the units of armed forces seemed almost endless, although many were clearly recently uniformed secondary school students, some as young as 15, who are being trained to be a part of an armed populace that Qaddafi has said will take over from the Army in the future.

The vast parade was followed by an impressive display of Qaddafi's latest acquisitions from the East: 350 new Soviet-made multiple rocket launchers mounted on trucks and armored cars. The rocket launchers are known eolloquially as "Stalin's organs." They were so new that many still had shipping wrapping paper wound around their sights.

The parade was followed by a small flyby of six Mig21s, a sign that for all the mobilized foot soldiers in the streets, Libya might still be short of trained pilots for its vast Air Force.

Qaddafi -- who had worn a khaki dress uniform with a gold-braid decorated officer's hat jammed rakishly low over his eyes for the military parade -- returned to the Green Square this evening for a second parade, this time of armed militias, professional groups, unions and civil servants.

He arrived bareheaded and wearing an open-necked combat blouse with his colonel's stars on his epaulets.

Arriving in the square, his open-topped vehicle was mobbed by crowds of well-wishers who pushed and shoved against the Libyan leader's security guards to grab at Qaddafi's proferred hands.

Qaddafi, his long, curly hair standing out like an Afro, was clearly delighted by the reception. He beamed, waved his fists in the air, smiled and wiped the sweat from his brow.

He watched the second parade march past, then delivered his speech before a bank of five microphones. He spoke of making Libya industrially strong to defend its revolution.

But it was his message of military strength -- in terms of men as well as weapons -- that he sought to underline. It was an obvious reaction to criticisms that had been leveled at him about Libya's lack of trained manpower despite the sophisticated weapons its oil wealth has been purchasing for the past decade.

"Let us all be clear about one thing," he said. "We will export our revolution everywhere, to every country that opposes us."