“This is an area that I’ve been concerned about,” the president said. “Look, Israel is a robust, rowdy democracy. ... We share so much. We share blood, family. ... And part of what has always made the U.S.-Israeli relationship so special is that it has transcended party, and I think that has to be preserved. There has to be the ability for me to disagree with a policy on settlements, for example, without being viewed as ... opposing Israel. There has to be a way for Prime Minister Netanyahu to disagree with me on policy without being viewed as anti-Democrat, and I think the right way to do it is to recognize that as many commonalities as we have, there are going to be strategic differences. And I think that it is important for each side to respect the debate that takes place in the other country and not try to work just with one side. ... But this has been as hard as anything I do because of the deep affinities that I feel for the Israeli people and for the Jewish people. It’s been a hard period.”

You take it personally? I asked.

“It has been personally difficult for me to hear ... expressions that somehow ... this administration has not done everything it could to look out for Israel’s interest — and the suggestion that when we have very serious policy differences, that that’s not in the context of a deep and abiding friendship and concern and understanding of the threats that the Jewish people have faced historically and continue to face.”

As for protecting our Sunni Arab allies, like Saudi Arabia, the president said, they have some very real external threats, but they also have some internal threats — “populations that, in some cases, are alienated, youth that are underemployed, an ideology that is destructive and nihilistic, and in some cases, just a belief that there are no legitimate political outlets for grievances. And so part of our job is to work with these states and say, ‘How can we build your defense capabilities against external threats, but also, how can we strengthen the body politic in these countries, so that Sunni youth feel that they’ve got something other than [the Islamic State, or ISIS] to choose from. ... I think the biggest threats that they face may not be coming from Iran invading. It’s going to be from dissatisfaction inside their own countries. ... That’s a tough conversation to have, but it’s one that we have to have.”

That said, the Iran deal is far from finished. As the president cautioned: “We’re not done yet. There are a lot of details to be worked out, and you could see backtracking and slippage and real political difficulties, both in Iran and obviously here in the United States Congress.”

On Congress’s role, Obama said he insists on preserving the presidential prerogative to enter into binding agreements with foreign powers without congressional approval. However, he added, “I do think that [Tennessee Republican] Senator Corker, the head of the Foreign Relations Committee, is somebody who is sincerely concerned about this issue and is a good and decent man, and my hope is that we can find something that allows Congress to express itself but does not encroach on traditional presidential prerogatives — and ensures that, if in fact we get a good deal, that we can go ahead and implement it.”

Since President Obama has had more direct and indirect dealings with Iran’s leadership — including an exchange of numerous letters with Iran’s supreme leader, Ayatollah Ali Khamenei — than any of his predecessors since Iran’s revolution in 1979, I asked what he has learned from the back and forth.