Washington ? Hopefully we won’t see a Middle East replay of the “The Guns of August,” as Barbara Tuchman titled her famous account of the slide toward World War I. But the region is edgy this summer as negotiators struggle to resolve confrontations with Syria and Iran.

One small sign of the rising tension is that Saudi Arabia is said to have alerted some of its military and security officials to cancel their planned summer leaves. According to Saudi and U.S. sources, this limited mobilization reflects worries about possible military conflict with Iran, the war of succession in Syria, and Sunni-Shiite tensions in the neighboring state of Bahrain.

Diplomats are working overtime to defuse these regional crises, but so far without success. Kofi Annan, the former U.N. secretary-general, has led an international effort to broker a political transition in Syria, but this hasn’t budged President Bashar al-Assad. Annan said Monday that he’d had “constructive” talks with Assad and would soon present proposals to the Syrian opposition. But it’s depressing how little headway Annan has made despite broad international agreement that Assad should go.

On the Iranian front, talks are continuing with the P5+1 group over controls on Tehran’s nuclear program. This effort is backed by the five permanent members of the Security Council, but meetings in Istanbul, Baghdad and Moscow have produced little beyond an exchange of paper. Talks are continuing among technical “experts” who perhaps can explore a deal outside the parameters of the canned negotiating scripts.

Certainly, this will be a summer for diplomatic brinkmanship. Assad’s leverage is his threat to take Syria down with him in a sectarian civil war. The optimal solution would have been a Russian-brokered transition of power, but the window for such a deal is closing. At some point, a “peaceful transition” will be impossible with so much blood spilled. Russia appears, finally, to be backing away slightly from Assad, refusing to sell him more weapons, but is it too late?

The Iran negotiations are also driven by the prospect of war, if diplomacy should fail. U.S. analysts believe that the past three months of talks should at least have convinced the Iranians that their bargaining position is weak. Tehran’s hard line hasn’t prevented the imposition of new sanctions, it hasn’t amplified Europe’s economic jitters, and it hasn’t fractured the P5+1 coalition. Now the real bargaining begins, in the view of some U.S. and European officials, with economic sanctions adding more pressure on Tehran every day.

Going to the brink is part of many negotiations, and usually the parties reach agreement and avoid disaster. But not always: Henry Kissinger, the former secretary of state, told a gathering of Harvard students a few months ago that if the statesmen of 1914 had known what the world of 1919 would look like, they surely would have made different decisions. But statesmen never have such foreknowledge.

The diplomat’s faith that compromise emerges in the heat of crisis unfortunately isn’t supported by recent evidence. The European Union has held 19 summits since the eurozone crisis began three years ago, and there’s still no resolution. In America last year, even the specter of financial default wasn’t enough to get politicians to reach more than a temporary agreement.

Strategists for decades have studied the factors that drive nations toward conflict. One lesson of 1914, for example, is that it’s important to avoid an automatic process of escalation, in which one side’s mobilization compels a countermobilization by the other side. That makes me worry about the Saudi alert. Another precept for crisis managers is the need for quick communications links — like the famous “hotline” that was installed between the White House and the Kremlin after the 1962 Cuban missile crisis.

Once the process of escalation begins, it may be hard to stop. In Syria, many analysts believe that the level of sectarian killing is already past the tipping point; there are too many scores to settle. In Iran, the definition of the crisis is the lack of trust between Tehran and the West. There’s too little mutual confidence even for a hotline.

The Obama administration has opted to work with international coalitions to confront Syria and Iran. This still seems like the most sensible policy. But if these multilateral efforts are failing, it will fall to the United States to devise an alternative strategy. If the U.S. wants to get to “yes” in these negotiations, it will have to bargain more independently and aggressively.