Muhammad steered his car casually into the intersection to find his path suddenly blocked by a tall Israeli soldier.
''It is forbidden,'' the soldier shouted and waved him back.
''Why?'' asked Muhammad.
The soldier merely barked louder and gestured violently that the car should retreat. Shrugging, Muhammad put the red Mercedes into reverse.
''It used to be the Syrians . . . now it is the Israelis,'' he said.
His comment captured the mood of west Beirut residents when they peeked out of their basements Thursday to find their city occupied - again. Two days earlier, they had been hoping the days and nights of cowering in shell- and bullet-smashed buildings were over. But on Thursday the city was again a battlefield.
People climbed out of their shelters in mid-afternoon looking dazed and depressed. One prominent newspaper columnist kicked his way through the glass littering west Beirut's main street, Hamra, and stared at the Israeli tanks parked on the corner.
''The battle is over and Lebanon is finished forever,'' he said with a great sigh of resignation.
But the Lebanese, after more than seven years of war and bloodshed beyond the comprehension of most nationalities, are champion survivors.
Within two hours of the Israelis wiping up all but a few pockets of resistance from mostly young leftists equipped with nothing more than assault rifles and rocket-propelled grenades, the city sprang to life again. The bodies of T-shirted teen-age warriors shot down in their tennis shoes were still sprawled in the streets as people began walking their dogs and having coffee with the neighbors.
People streamed up and down Hamra, picking their way through the debris of the battle, oblivious to the occasional distant explosion. They were somber, their arms hanging loosely as if their strength had been sapped.
Most of the strollers were men. Almost without exception they bunched on the street corner to gape at the two Israeli tanks nestled under a tree. If they walked past the Israelis, they kept a guarded distance even though they stared.
Many ordinary folk admit they think of Israelis as almost having horns and tails. And the Israeli soldiers, stationed until Thursday on the capital's outskirts, used to ask reporters questions about the people of west Beirut and the Palestinians as if they, too, conceived of ''the enemy'' as scarcely human.
Soon a waiter ventured out of his restaurant and offered Arabic coffee to the Israelis. His expression and manner didn't look as if he had done it because he was pleased to see them. He acted much more like a man who thought he should accept and benefit, if possible, from the new fact of life.
That man was a typical Lebanese.
The Israelis began their push into west Beirut on Wednesday, but during the night pulled back from their advance position to protect themselves. By nightfall Thursday, they were still fighting in some spots and were edgy and watchful. However, their posture in the rest of the city was fairly relaxed. They did not seem too concerned about stray snipers or militia men.
Even in south Lebanon the pattern has not been immediate hit and run attacks on the Israeli occupation forces. Beirut is likely to follow suit.
The population is very weary after more than three months of war, often combined with siege. There are bound to be incidents. But the war-wise residents of west Beirut know they are licked.