Saying that Yasser Arafat appears to have little or no control over Islamic Jihad in no way lessens the hideousness of the most recent attacks in Israel, in which 17 Israelis, including 13 soldiers, were killed Wednesday when a bus was bombed. But it should change Israel’s response, which was to attack Mr. Arafat’s compound in Ramallah, while Islamic Jihad leader Sheik Abdallah al-Shami in Gaza was boasting to the press about his group’s intention to continue its violent activities no matter what the Palestinian Authority said or did.

Pressuring Mr. Arafat over the Islamic Jihad bombing makes sense politically. It exposes his leadership either as corrupt by demonstrating that his comments against the suicide bombings are insincere or as irrelevant to further negotiation. Israeli pressure on Mr. Arafat increases the need for Palestinians to decide whether their leader is capable of offering a means to peaceful co-existence.

Israeli forces, according to news reports, has been effective in recent months against Hamas; they should have U.S. support to defend Israel against Islamic Jihad’s plans. Writing in the New York Times a couple of months ago, former Prime Minister Ehud Barak described three pillars of an Israeli strategy: “a tough campaign against terror, an open door for resumption of negotiations and physical disengagement from the Palestinians.” He emphasized the third point – guarded fences that would take in seven settlement areas in the West Bank – and provide a geographic break to dramatically reduce the killings and increase the opportunity for negotiation.

Fences are an interesting idea but their broader point is more important: The need for security – and not paper security but real physical security – to precede negotiation is essential. But the level of hope and the ability for a stronger civil society on the other side of such a fence could provide even better security. The United States has looked for ways to be helpful in ending the violence. Stronger U.S. support for Palestinian society while recognizing Israel’s right to be secure may be useful.