It’s getting to the point where it’s hard to be shocked by the attacks the Arabs premeditate against civilian targets. Recent targets have included a Passover seder, a wedding, a disco, the World Trade Center. Yesterday, it was a bus in Jerusalem, while as yet unknown killers struck at the United Nations headquarters in Baghdad. At least 18 people were killed in the Jerusalem bus bombing. The Associated Press reported that the bus had started out at the Western Wall, and that among its passengers were members of a family returning from celebrating a bar mitzvah there. The truck bomb in Baghdad killed at least 20, including at least 14 U.N. workers, according to the wire.

There are several facts worth keeping in mind about these bombings. The first is that responsibility for the Jerusalem bombing was claimed by both the Hamas and Islamic Jihad terrorist groups. The second is that at the time of the bombing, according to the Israeli daily Ha’aretz, the Palestinian Arab prime minister, Mahmoud Abbas, was meeting with Islamic Jihad representatives. Mr. Abbas’s public “condemnation” of the bombing will no doubt get public attention, but the Abbas-Islamic Jihad meeting would be a ripe topic for congressional hearings. What Mr. Abbas has promised to do is not to meet with the terrorist groups but to dismantle them. It’s a promise he has failed to keep.

Hamas and Islamic Jihad don’t operate in a vacuum. They get support from governments — most prominently Iran, but also the Palestinian Authority and Syria. Weapons and explosives are smuggled into place through Egypt and Syrian-controlled Lebanon. The perpetrators of the bombing in Iraq haven’t yet identified themselves. The New York Sun reported last week, however, that Iran, Syria, and Saudi Arabia are conspiring with loyalists of Saddam Hussein to try to make sure that America follows in Iraq the example of America in Somalia, Beirut, and Vietnam — bleed and flee.

The alternative is to stay and win. That means expanding the conflict from Iraq and Israel to include Syria, Iran, and eventually Egypt and Saudi Arabia. It doesn’t necessarily mean American invasions of all those countries — in many of them, particularly Iran, free and democratic opposition forces are standing by. This goes, as well, for the Palestinian Authority, where it’s well past time for America to arrest or exile Yasser Arafat and his crony Mr. Abbas and begin dealing instead with genuine reformers. The notion that America should go ahead and, as Mr. Bush has proposed, dedicate tens of millions of our taxpayer dollars to strengthening Mr. Abbas’s regime has long since been disgraceful, but never more so than in the wake of yesterday’s bombing and the meeting with Islamic Jihad.

Had America followed the path counseled by the free Iraqi opposition during the 1990s and given the Iraqis themselves the lead in liberating their country, we’d have fewer American troops in harm’s way there today. An Iraqi force would also have to face less resistance to “occupation,” and its language skills and local knowledge would allow it to do better than Americans in pacify ing the country.

That is the strategic calculus. The political calculus is what interferes. President Bush and his advisers seem at times to want an intermission in the war on terrorism. The first phase — in which Mr. Bush was an inspiring and steely leader — included Afghanistan and Iraq. The intermission would include Mr. Bush’s re-election, along with a focus on the American economy and a consolidation of the gains in Iraq and Afghanistan. And the second act might include Iran, Syria, and North Korea, with Egypt and Saudi Arabia as the third act.

With Western corpses piling up at yesterday’s rate of 38 a day, the cost of an intermission is too great. President Bush’s father stopped short of full victory in the 1991 Gulf War. It helped cost him the election and put the Iraqi people and the world at risk for another decade — a decade that included September 11, 2001. If Mr. Bush delays the drive for full victory now, we can all expect more days like yesterday, watching the body bags and the ambulances full of innocent Western civilians crowd the sites of terrorist attacks.