Sen. John McCain, right, as he endorsed Mitt Romney's bid for the presidency earlier this month.

STEVE INSKEEP, HOST:

The wave of protests we call the Arab Spring is just one of many factors American foreign policy experts have to keep in mind as they review a changing world. Just this week, the Pentagon has been detailing plans to shift U.S. strategic priorities, moving more attention to the Pacific and saving money by reducing the size of the military. Senator John McCain has been watching those changes with some skepticism. The Republican presidential nominee from 2008 is unsure of plans to shrink the military, and he's also thinking of risks, like confrontation with Iran.

SENATOR JOHN MCCAIN: It is a situation that is nearing crisis proportions. I'm not saying it's at a crisis, but it certainly is a lot closer than it was a year ago.

INSKEEP: McCain does not say war is imminent but argues it is possible. Iran has denied it's seeking nuclear weapons but has come to no agreement with doubters in the West who want Iran to stop enriching uranium. We sat down with the Senator McCain yesterday at his office on Capitol Hill.

MCCAIN: It is a fact that with all the sanctions and all the other efforts we've made, both diplomatic and with our alliance and with the European Union, that the Iranians have not been deterred from their path towards the acquisition of nuclear weapons. It's just a fact. So that does raise the threat or the possibility of Israeli slash perhaps even U.S. military action to prevent Iran from acquiring nuclear weapons. The president said we will not allow Iran to do that. When the president of the United States says that, it means that all options are on the table.

INSKEEP: I would like to get you to expand on that phrase, if I might. President Obama must say all options are on the table, as president probably cannot say anything much more detailed than that. You're in a position to help us think this through. We know where we are now. These sanctions are in place. They may be increased in the next few months. What options are there?

MCCAIN: It's complicated by it's not just the United States' decision. It's also an Israeli decision. Israelis have stated unequivocally that a nuclear-armed Iran is an existential threat to the state of Israel. It's also complicated by the fact that the Iranians have made use of this time to both disperse and to heavily imbed their nuclear facilities, in one case deep in a mountain, which makes the military equation extremely complicated. So there have been some interesting mishaps that the Iranians have suffered and the untimely deaths of some of their scientists and a virus that we all know about.

INSKEEP: You're talking about the Stuxnet virus, the computer worm that hit the computers, the assassinations of a number of scientists.

MCCAIN: Yeah. But I do think it has probably had some effect in slowing down their effort. Now, there's no doubt that the sanctions are squeezing the Iranians now. But the most likelihood that the Iranians will be dissuaded from the path they're on is the more certainty they have that they will pay a very heavy price for it.

INSKEEP: Some of the Republican presidential candidates, as you know, Senator, has criticized President Obama's approach to Iran. In your judgment, has this administration been tough enough?

MCCAIN: I think that history will judge this president incredibly harshly, with disdain and scorn for his failure to come to the moral assistance of the 1.5 million Iranians that were demonstrating in the streets of Tehran, crying out, literally crying out Obama, Obama, are you with us, or with you - are you with them?

INSKEEP: After the disputed election in 2009.

MCCAIN: If we had given them some moral support, it might have made a difference. Disgraceful, a violation of everything that we've ever stood for. And at the time I complained bitterly about it. And I must say that the liberal media all criticized me. But that's neither here nor there. But the point is, we had an opportunity there. That window was shut.

INSKEEP: What about the argument that the president has been carefully aligning other nations against Iran, building up coalitions, and now there are sanctions that are really closing in on Iran?

MCCAIN: I think that the president and the administration has done a pretty good job on sanctions, but the fact is, who's blocking the sanctions? Russia and China. We should make it very clear to the Russians and the Chinese, if this is the threat that generally has been agreed upon, then we should be telling the Russians and the Chinese that their failure to support strong action in the U.N. Security Council will have a direct bearing on our relations with these two countries. The president's been very weak on that.

INSKEEP: We've been hearing that the Chinese have been cutting back their imports of Iranian oil. Are they not being helpful in this situation?

MCCAIN: The Chinese are cutting back on their purchases of Iranian oil because they are concerned about the fact that Iranian oil may be cut off, and nothing to do with their desire to assist us in preventing what could possibly be a conflict.

INSKEEP: We're talking with you, Senator, during this week when you're doing some campaigning for Mitt Romney in Florida. Your name has come up in the presidential campaign in this way in the last couple of days. Mitt Romney has released a couple of years of tax returns. It's been pointed out by Democrats that when you were vetting him as a possible presidential candidate, that you got 23 years of his tax returns. Has Governor Romney disclosed enough tax information, having given up two years?

MCCAIN: I think he's disclosed enough. You know, we vet people when we're considering people for vice president, but very frankly, I never looked at his tax returns. That wasn't my job or my priority at the time nor should it be.

INSKEEP: What should people make of his wealth? There's been so much discussion of it.

MCCAIN: Well, first of all, I think it's a great success story in many respects. It certainly is a way of business creating jobs as opposed to government creating jobs. That's going to be, I think, one of the central parts of the debate when he wins the nomination, and I think he will.

INSKEEP: Senator McCain, thanks very much.

MCCAIN: Thanks for having me on.

INSKEEP: That's Arizona Senator John McCain, the leading Republican on the Armed Services Committee, on NPR News. Transcript provided by NPR, Copyright NPR.