May 15th 2011, 19:49 by D.L. | JERUSALEM
ON SUNDAY Israel got an unexpected and unpalatable taste of its nightmare scenario: masses of Palestinians marching, unarmed, towards the borders of the Jewish state, demanding the redress of their decades-old national grievance.
In three separate episodes during the day—on the Syrian border with the Golan Heights, on the Lebanese border and on the border with the Gaza Strip—those marching were met with live gun fire. At least a dozen Palestinians died. Scores more, most of them young men, were injured.
Israeli police and Palestinian demonstrators traded stones and tear gas in East Jerusalem on the third day of street violence following the death of a young Palestinian, apparently shot by a settler or a security guard. Many were injuried and dozens arrested, but no more fatalities were reported.
Meanwhile in Ramallah, the de facto capital of the West Bank, thousands of people marked "Nakba Day", the anniversary of Israel's creation in 1948, in a huge gathering organised by the Palestinian Authority.
Nakba Day, falling close to Israel's independence day (which was celebrated last week), has often been a time of particular tension in the occupied territories and inside Israel-proper. This year police inside the country and the army in the West Bank were placed on high alert. Israel is worried that the Arab spring that is sweeping the region, and the Palestinian leadership's plan to seek statehood at the United Nations in September are likely to inflame popular emotion and lead to violence on the West Bank and possibly also in Israel.
The prospect of mass, unarmed "invasions" by refugee Palestinians from across the borders, though much discussed as a doomsday scenario, was apparently not seriously contemplated by the army. As a result, when a couple of thousand Palestinians, bused to the Golan border opposite the town of Majdal Shams, began clambering over the fence, only a small force of soldiers confronted them.
"I ordered the army to exercise maximal restraint," said Israel's prime minister, Binyamin Netanyahu, in a brief televised announcement in the evening. "But no-one should be mistaken; we are determined to defend our borders and our sovereignty."
On the Golan border, several Palestinians were shot dead. But the Israeli officer in command decided not to fire wholesale, and hundreds of people eventually poured through the broken fence and into Majdal Shams. Local residents, Druze citizens of Syria who live prosperously but carefully under Israeli occupation, rounded them up and escorted them firmly back over the border. "We’re not happy about this," Dolan Abu Salah, the town's mayor, told Israeli television.
On the Lebanese border, near the Israeli village of Avivim, Lebanese troops shot into the air in an effort to deter the crowd of Palestinians. When they approached nevertheless, Israeli soldiers fired, killing as many as ten people according to Lebanese reports. The fence was not breached.
On the Gaza border, the army said it had killed one man seen laying an explosive device. At least one other fatality occurred when a crowd of Palestinians marched towards the main checkpoint at Erez Crossing and Israeli troops there opened fire.
Israeli officials claimed to see the hand of Iran or Syria's beleaguered president, Bashar Assad, in the Golan and Lebanon border incidents. They pointed to the relative quiet on the West Bank, despite fears of serious disturbance there.
But behind the brave facade, many in Israel are seriously worried that the powerful phenomenon of masses marching in defiance of armed force may at last be spreading to Palestine after challenging so many regimes in the region.
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