The 20th century was a century of war. In August 1914, the peace of Europe was shattered. The United States, which had remained apart from major foreign wars for a century, was drawn in.

Tragically, the United States has been at war many times since then: World War II, Korea, Vietnam, Iraq and Afghanistan. It is not something Americans a century ago would have expected when they thought World War I would be the “war to end all wars.”

The 21st century, unfortunately, does not look any better. Having inherited two wars, President Obama is trying to extricate America from one war in Iraq to concentrate on another in Afghanistan. But a third war is looming: Iran.

Despite the talk about all options being on the table, the United States is not in any condition to engage in another conflict. And certainly, the United States does not want war. But the United States may not be able to control events. Ominously, statements emanating from the Middle East highlight the possibility of conflict this summer.

“If something doesn’t happen until July, we’re in trouble,” Jordan’s King Abdullah recently told the Chicago Tribune. “If we hit the summer and there’s no active (peace) process, there’s a very good chance for conflict.” Abdullah’s statement is not the only one. “The best way to stop war is to prepare for it,” Galal Nassar wrote in Egypt’s Al-Ahram Weekly last March. “The Arab League Council decision [to negotiate for four months] has brought us closer to war. In four months time we will be closer still.”

A columnist in an Egyptian newspaper does not have the same authority as a king, but remarks of this sort in such a prominent medium should not be taken lightly. Do they foreshadow a change in Egyptian policy, or do they signify dissent within the regime? Whichever it is, Nassar’s assessment underlines the importance of this summer.

Jordan and Egypt are the two Arab countries that have peace treaties with Israel. If they now feel the situation is so urgent, it raises questions about how long any peace can hold.

Perhaps the most definitive statement, however, comes from Iranian President Mahmoud Ahmadinejad. According to a report in the pan-Arab newspaper Al Quds Al Arabi that was summarized in the English language National, at a meeting in Damascus last February President Ahmadinejad told Syrian President Bashar Assad and Hezbollah leader Hassan Nasrallah that he expected war to break out sometime between spring and summer of this year.

Indeed, preparations for war on both sides seem well under way. The Iranians recently completed major naval exercises in the Persian Gulf, and the Israelis have revealed new capabilities for striking targets at long range.

The conflict does not have to begin with an attack on Iran. The border between Israel and Lebanon, which was the site of a war four summers ago, is once again looking dangerous. Reports that Hezbollah now possesses Scud missiles, whether true or not, add to heightening tensions.

The challenge here is not only for the United States, but for Israel. It is, first of all, a conceptual challenge.

In Israel there is a growing sentiment that its conflict with the Palestinians is not ripe for resolution, but that it can be successfully managed. The sense of urgency evident in King Abdullah’s warning does not seem to exist. This is a huge and potentially dangerous disconnect, as it may lead to miscalculation. In 1914, Austria miscalculated. The government in Vienna did not imagine when it delivered its ultimatum to Serbia that it had set in motion a chain of events that would culminate in its own destruction.

Which brings us to the question we confront now.

If there is another war in the Middle East, will it remain limited like previous ones, or will it draw in other participants who feel they can no longer stand aside? Will governments be able to restrain the emotions of people who feel they will be dishonored if they don’t support their brethren?

So far, the 21st century has been characterized by war.