The emerging Iran deal that the Obama administration contends is comprehensive and definitive contains so many uncertainties, including those regarding Iran’s future nuclear weapons aspirations, that it might well turn out to be an extended interim accord.

This underscores an issue with a few things Secretary of State John Kerry recently said while defending the Iran deal–remarks that I presume he’d like to take back:

“President Obama has absolutely pledged they will not get a nuclear weapon” and “We will have inspectors in there every single day. That is not a 10-year deal; that is forever.”

I understand the administration’s need to market the Iran deal and why senior administration officials might get carried away with their handiwork. They believe that they know what’s best for the nation.

What’s harder to explain is the way that this administration processes time, and the durability of any agreement, particularly in relation to a turbulent region where time is measured along a more extended arc. In the Middle East, there is no “forever,” certainly not when it comes to the designs of external powers that seek to meddle in or impose their will on the affairs of small tribes. Consider:

All U.S. administrations measure their lives in four- and, if they’re lucky, eight-year increments. They need to get things done quickly. President Barack Obama was ready to declare the war on terrorism over in 2012; three years later, he is more immersed in it than ever before. The same is true of the U.S. exit from Iraq in 2011; now we’re back in, albeit in a different role. With the U.S.-backed NATO intervention in Libya, there was commitment on the front end but little follow-up. The United States is not really good at following up. We grow tired and disillusioned as things get too hard, and come to feel that it’s really not our neighborhood or our fight; along with expecting results that are not realistic.

But in the Middle East, the nations and leaders we deal with have watched U.S. presidents and secretaries of state come and go. Because they see their struggles in terms of regime survival–to preserve their physical existence, political identity, and religious identity–there is much less urgency, greater caution, and more continuity. Since its 1979 revolution, Iran has had two supreme leaders; the U.S. has had six presidents. Yasser Arafat dominated the Palestinian national movement for half a century; the military controlled Egypt since the 1952 revolution to the Arab Spring and the Muslim Brotherhood interludes, and controls it still. This is very different from “administration time.”

Even the democratic Israelis, who operate in political time closest to ours, take a longer view. Hard-line prime ministers such as Yitzhak Shamir, Ariel Sharon, and Benjamin Netanyahu see time as an ally, not an adversary. Peacemakers such as Yitzhak Rabin preferred Oslo’s incremental approach to change. Ehud Barak was bolder and more risk-averse in peacemaking with the Palestinians; and that could be one of the reasons he was defeated by Mr. Sharon in 2001 in one of the biggest electoral losses in Israel’s history.

Arab authoritarians dominated the Middle East for half a century. But recent events remind us that the only thing one can be certain of in today’s Middle East is change. Although al-Qaeda core has been dismantled, derivatives such as al Qaeda in the Arabian Peninsula remain serious threats. Islamic State’s tyranny–the same group President Obama called a “JV” team last year–threatens Iraq, Syria, and beyond. Only time will tell how this all turns out. And given the history of this region, that’s not reassuring.