Sergei Grits/AP Photo

This week, we asked Foreign Policy Initiative Co-Founder Dan Senor to answer five questions. Dan will join the discussion on our powerhouse roundtable Sunday on "This Week."

1) How would you grade President Obama in terms of his overall foreign policy?

Recall the foreign policy goals that then-candidate Obama proclaimed he would advance as president. He said he would restore America's image abroad, especially in the Muslim world; forge a lasting peace between Israel and the Palestinians; wind down the war in Iraq in order to re-focus on Afghanistan; recalibrate America's relationship with Iran though personal diplomacy; usher in a new era of cooperation with China; and, fundamentally "reset" relations with Russia. Graded against the expectations that he set, perhaps his failures were inevitable. Success on any one of those fronts would have been an impressive achievement. That he hasn't really re-calibrated his approach in spite of persistent failures should worry us about the next few years.

There is of course another standard by which American foreign policy should be judged: is the world a more stable place? In the run up to the 2012 election, the President repeatedly proclaimed: "The tide of war is receding." But from Damascus to Sevastopol and Beirut to Baga, it appears as if the "tide of war" is rushing in again. In the vast majority of countries you can name - including Iraq, Israel, Saudi Arabia, Egypt, Jordan, and the United Arab Emirates, to take just a handful in the Middle East - relations with America are worse than they were when Mr. Obama took office. Certainly the Middle East is more unstable. And Vladimir Putin has unfortunately had his way with President Obama on issue after issue, whether it has to do with arms control agreements, Crimea and Ukraine, Syria and Iran, or providing a safe haven to Edward Snowden.

2) You advised Mitt Romney on foreign policy during his campaign for president and he recently wrote an op/ed for the Wall Street Journal slamming President Obama. Is there any reason to think that Russia would not have seized Crimea if Mitt Romney was in the White House? How would that have been prevented?

It's impossible to know. But when surveying the many trouble spots today, Mitt Romney was right to ask, "Why are there no good choices?" When President Obama ran for re-election he didn't say, "Look, foreign policy is tricky, I don't have a lot of good options." He ran on a platform of foreign policy achievements. The gist of his argument was: "We ended the war in Iraq. Al-Qaeda is on the run. We're stopping Iran. I've restored America's standing with the international community….And if you elect Mitt Romney, he'll undo all these things." After all, it was only a few months ago that the President gave a press conference where he said the reset with Russia had "succeeded." Recent events have proven this rhetoric to be empty. And Governor Romney's point of criticism - that America now lacks credibility as a consequence - is spot on.

Vladimir Putin invaded the Ukraine because he perceived he could advance Russian interests at no real cost. He didn't go in because of, or to spite, President Obama. But he did calculate what President Obama's response was likely to be. In making that calculation it's reasonable to assume that Putin weighed Mr. Obama's previous words against his deeds. He had only to look to Syria to see the disconnect between what President Obama said would happen if a tyrant crossed a red line and what actually did happen when a tyrant crossed that red line. To make matters worse, this has all occurred against the backdrop of record cuts to our defense budget, which sends a signal of weakness to our adversaries (and our allies) as well.

Effective deterrence is a function of credibility and credibility rests in large part on the perception that America will act to uphold its interests and its commitments. The less credible a President's word, the less America's ability to deter by threatening consequences. So, do I believe a Romney administration would have carried more of a deterrent? I do. And not because Governor Romney would have resorted to force, but because bad actors would have considered plausible the possibility that he might resort to force; and if not military force, then certainly a more vigorous and determined response than what we've seen from President Obama.

3) What's your assessment of the current push by the Obama administration to achieve a peace agreement between the Israelis and the Palestinians? Are you optimistic?

I think the timing is all wrong and it shows a disconnect with realities in the region. Talk to the Saudis, the Emiratis, and the Turks about what should be the focus of American diplomacy right now. Syria is disintegrating, Iraq is unraveling, Egypt remains on the precipice, and Iran moves closer to a nuclear bomb. How those situations are resolved will do more to shape the future of the Middle East than negotiations between Israel and the Palestinians. And the reality is that leaders across the Middle East are far more concerned with how those situations will be resolved.

So the regional environment gives me little cause for optimism right now. But I'm also highly skeptical for another reason. History shows that those presidents who have had strong relationships with their Israeli counterparts are best able to convince Israelis to make sacrifices in the hope of peace. Can you imagine the Oslo accords without Bill Clinton's relationship with Yitzhak Rabin? Can you imagine Ariel Sharon having withdrawn from Gaza if he wasn't convinced that George W. Bush would stand with Israel? President Obama has dictated more demands to Israel than any other president in recent memory. And at the same time, he has had one of the most contentious relationships with an Israeli premier in recent memory. Mr. Netanyahu was left in the dark about the U.S. negotiations with Iran. Do you think that gave the Israelis a sense of security? Fundamentally, if there are questions of trust between the President of the United States and the Prime Minister of Israel, I don't think that's a formula for a successful peace process. It's the opposite, in fact.

4) Your take on Rand Paul's foreign policy? Does his approach help or hurt him should he run for president?

Senator Paul went to Berkeley last week to give a speech that the press characterized as "courageous." He went right into "the lions' den," it was said. Really, now? The truth is Senator Paul went to Berkeley and criticized America's intelligence community and America's war on drugs. It's hardly an act of bravery to say those things on the Berkeley campus.

While foreign policy is rarely the top concern for voters in a presidential election, candidates do have to pass a critical litmus test: would you trust them as commander-in-chief? On most foreign policy issues, Senator Paul is outside the mainstream. Take Iran. Polls show that a majority of voters would support American military action against Iran as a last resort if that's what it took to stop their acquiring a nuclear weapon. Such action would be, from what I can tell, unacceptable for Senator Paul. In fact, he's repeatedly opposed Iran sanctions bills that have sailed through House and Senate with huge bipartisan majorities. Similarly, so long as voters believe in a "strong military," Senator Paul's support for dangerous defense cuts will hurt him in a GOP presidential primary.

Rand Paul has also been all over the map during the Ukraine crisis. At first he chided fellow Republicans for holding a "Cold War" mentality, for failing to recognize Russia's "long history" in the Crimea, and warned against "tweaking" Russia. But just days later he'd done a complete 180, criticized Obama's weak handling of the situation, called out Putin's "gross violation" of Ukrainian sovereignty, and demanded Russia's international isolation.

Overall, I think the press confuses GOP voters' distrust of Mr. Obama for a drift towards quasi-isolationism. I have seen relatively little evidence that the GOP is heading in the direction. What I do see is a deep distrust of Obama running our foreign policy.

5) What's the biggest foreign challenge facing the United States that gets too little attention in your view?

The Iranian issue can't get too much attention. And given the perilous state of global affairs, Iran is all too regularly pushed from center stage, assuming the form of just one more troublesome foreign policy issue where America has "no good choices." A nuclear Iran would fundamentally alter the balance of power in the Middle East while simultaneously eviscerating America's credibility in the region. It would set off a nuclear arms race in the least stable region in the world. And it would entrench and embolden an Islamic regime whose stated desire is to wipe Israel from the face of the map.

There are those who proclaim that a nuclear Iran can be contained. Those same voices said Bashar Assad would never use chemical weapons. Those same voices fail to consider that a regime ceases to act rationality when pushed by revolution beyond the brink of self-preservation. But most importantly, those same voices fail to take into account America's track record in containing a conventionally armed Iran. A conventionally-armed Iran has killed American troops in Iraq and Afghanistan, carried out acts of terrorism around the globe from Buenos Aires to Beirut, and through its proxies in Lebanon and Gaza has continually waged war with Israel. A conventionally-armed Iran hangs homosexuals from cranes, mows down student protesters, and tortures free thinkers.

If you aren't too concerned with the conduct of a conventionally-armed Iran, you're perhaps not too bothered by the prospect of a nuclear Iran. But when I think about the challenges that America faces, that's the one that's most terrifying. I really do believe that how we meet this challenge will go a long way to determining the stability of the world in which we live, and in which our children grow up. It's a threat unlike any other in the world today.

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