Is the U.S.A

For Israelis abroad, a new state of siege has begun. Their embassy in Washington, the U.N. mission and consulates in nine U.S. cities were put under increased protection after two weeks of anti-Jewish bombings. In New York City an after-midnight caller to the FBI warned of possible car bombings at two Israeli offices. The city responded by increasing patrols around Israeli buildings and blocking entrances with concrete barriers and trucks loaded with sand.

More than 100 representatives of New York's Jewish community gathered at city hall for a security briefing. Senior police officers told them that "based on all the things happening in the world right now," the city was taking the threat seriously. Though Israeli targets seemed to be most at risk, everyone was urged to be vigilant. "To the best of our knowledge," said Michael S. Miller, executive director of the Jewish Community Relations Council, "there have been no threats directed at the Jewish community." But as the bombing of the World Trade Center reminds Americans, almost anything could become a target.

Fighting the faceless terrorists will be no easier this time around. Israeli, American and British officials are convinced that the attacks in Buenos Aires and London, and possibly a bomb that destroyed a commuter plane in Panama, were the work of Iran's global network of killers. Obscure Lebanon- based affiliates of Hizballah have claimed responsibility, but most intelligence experts agree with Uri Dromi, the Israeli government spokesman. Said he: "We have no evidence to present in court, but still we see Iranian fingerprints." A defecting Iranian diplomat has told Argentine officials that the blast in Buenos Aires was directed by a military attache and a cultural attache at the Iranian embassy.

Regardless of who is sponsoring them, the apparently coordinated explosions in several countries provide clear warning of more. "We don't know if this current wave is over," says an official in Washington. Says another government expert on terrorism: "We know that Hizballah has established an infrastructure in the U.S. and Canada. You have reason for concern."