Israel's attack last week on the ship bearing people bringing aid to Gaza, killing nine, has left Middle East relations and prospects for pursuing a peace process in shambles.

The question now is how to put that process, a piece of absolutely essential U.S. policy, back on track. Following are five suggestions:

• 1) The international community, led, if necessary, by the United States, must insist on the international inquiry into the May 31 incident called for by the U.N. Security Council. It was an international incident, involving a foreign-flagged vessel, that occurred in international waters in the Mediterranean Sea 75 miles off Gaza. The passengers were from many different countries. Nine people were killed, including a Turkish-American citizen born in Troy, N.Y. Israel plans only an internal investigation.

Israel also does not have a sterling record in such sea encounters. In 1967 it attacked a U.S. Navy ship, the USS Liberty, in the Mediterranean, killing or wounding more than a hundred U.S. sailors. The inquiry commission should include at least Israel, Turkey and the United States, the latter two countries having lost citizens in the incident.

• 2) If Israel continues to believe that a sea blockade of Gaza is necessary for its security, to assure that no lethal or security-related materials reach the enclave, the blockade should be enforced by credible international naval forces. The Quartet plus Israel and Turkey would be ideal for the task. The Quartet, which has been trying to move forward the Middle East peace process, comprises the United States, the European Union, Russia and the United Nations.

• 3) Seizing the initiative to restore decent relations between Israel and Turkey, damaged severely by this incident, President Barack Obama should invite Israeli Prime Minister Benjamin Netanyahu and Turkish Prime Minister Recep Tayyip Erdogan to meet with him at Camp David to seek to patch things up.

U.S. relations with Israel date from Israel's inception and remain close and virtually unshakable despite recent difficulties. U.S. relations with Turkey are almost as venerable and deep, although less visibly so.

Turkey is a fellow member of NATO. The United States worked closely with Turkish governments to help fend off attempts by the old Soviet Union to draw Turkey into its orbit. Turkish troops fought and died alongside Americans in the Korean War. The United States continues to support Turkey in its effort to gain membership in the European Union.

Turkey, a modern country with a Muslim majority, is a critical bridge between the West and the Muslim world, literally and figuratively. It has had decent relations with Israel across the years.

Mr. Obama would render a huge service to both if he can help repair those relations. An invitation to the two leaders to come to Camp David, with time set aside for them to hold one-on-one conversations, would help not only to fix things but would also put Mr. Obama in an excellent position to help move forward the lagging Middle East peace process.

If the president can manage to invite Dr. Henry Louis Gates Jr. and Cambridge, Mass., police Sgt. James Crowley to the White House for a beer summit to repair their relationship, he certainly can take action to try to salvage the relationship between Israel and Turkey, two old, important friends of the United States.

• 4) The United States needs now -- better late than never -- to establish lines to Hamas, the Palestinian organization that governs Gaza. If there had existed such a relationship before the Mavi Marmara sailed, the United States could have asked Hamas to ask the people on board to send their assistance by a means less likely to provoke a confrontation.

It is perfectly obvious that Hamas is not a group of nice people. They fire rockets into Israel and they have held an Israeli soldier captive for years, among their sins. Still, when the Palestinians voted in January 2006 in free, democratic parliamentary elections strongly supported by the United States, Hamas won.

TV interviewer Charlie Rose met in Damascus with Hamas leader Khaled Mashaal for an hour-long interview May 27. They did not agree on many points. It is difficult to imagine that a senior American representative, such as the U.S. special envoy to the Middle East, former Sen. George J. Mitchell, could not meet with Mr. Meshad privately in the interests of establishing communications that would enable all parties to a Middle East peace process to move forward and to avoid tragedies such as the deadly May 31 incident.

In any case, anyone who imagines that a Middle East peace process can move forward without Hamas at the table, in spite of the unacceptable positions it takes now, must have been into the medical marijuana. It is clear that the surest way to move Hamas into more acceptable positions is to be in contact with its leaders. Isolating them is just stupid on our part.

• 5) Finally, it is essential for U.S. interests across the world, including in the Afghanistan and Iraq wars, as some of our generals have pointed out, that a viable Middle East process be under way and have real prospects of success. Looking at the Mavi Marmara incident, it might be hard to see its having a useful outcome. On the other hand, if the death of the nine people results in Mr. Obama's firmly taking the lead now in putting the peace process on the rails, that will constitute a very positive outcome to a miserable business.

If Mr. Obama continues to stay away from this critical foreign policy issue out of fear of the Israel lobby, he will become just one more American politician afraid to take action necessary to achieve basic U.S. objectives in the world to instead pursue his personal ambitions. That would be too bad for all of us. The Mavi Marmara incident puts him, right now, at a major crossroads.

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