I always hesitate to write anything about problems in the Middle East because 1) it’s so difficult to sort out what’s really going on there, and 2) the issues seem so intractable. But the genuinely significant new nuclear agreement reached with Iran over the weekend merits brief comment regardless.

This agreement, limited though it is, represents a major diplomatic step forward in this troubled region. After 34 years of estrangement, the United States and Iran have reached an accord that seems almost epic given their turbulent relationship during that period. An academic historian at Johns Hopkins University quoted in The New York Times calls it “a historical deal” that represents “a major seismic shift in the region.” It is only a first step, of course, and one that already has plenty of critics, but it is proper, I believe, to read into it a movement toward accepting a degree of international responsibility on the part of Iran. It is, in short, a moment to be seized and built upon.

And doing that clearly will not be easy. Several US allies are opposed to any such agreement, most notably the Saudis and the Israelis (odd bedfellows, eh?). Given the very effective and influential Jewish lobby in Washington, the battle to conclude the accord will not proceed smoothly. President Obama already has spoken with Israeli Premier Benjamin Netanyahu, who calls the agreement “an historic mistake,” with the aim of convincing him that a longer-range solution for Middle East peace is more likely with an Iran that is a participant in the region’s future rather than an opponent to it. I believe it is strongly in the best interests of the United States, and therein lies our priority.

I also believe that any hope for a peace agreement between the Israelis and the Palestinians — a desirable goal that neither seems totally committed to making happen — will be ultimately abetted by further agreements with Iran, if that proves possible. And whether or not that happens is out of our control. If Iran’s government decides it is not willing to compromise further with its nuclear program, then everything will be doomed to failure. It’s worth proceeding on the assumption that this first step can lead to a second, and a third, however. We should all hope that diplomats of good will and commitment may generate something meaningful and lasting for the global community.

And when that’s done — could someone please try and put some sanity into our policy with regard to Cuba? It’s time — it’s so far past time — to place reason ahead of revenge and end our absurd estrangement with that nation 90 miles from our southern shores.