英语访谈节目:乌克兰武装会使俄罗斯放弃侵略还是使局势进一步升级?

GWEN IFILL: Should the United States beef up military support to Ukraine?

For that, we turn to Steven Pifer, who served as U.S. ambassador to Ukraine during the Clinton administration. He's senior fellow at the Brookings Institution. And John Mearsheimer, a professor of international security policy at the University of Chicago.

So what do you think is the answer to the question, Steven Pifer?

STEVEN PIFER, Brookings Institution: I think the answer is that we should provide additional military assistance to Ukraine, including some defensive arms, and that's designed to support the diplomacy.

It's designed to give the Ukrainians the ability not to beat the Russian army. They can't. But they can raise the costs to the Russians and therefore perhaps in the future deter Russian escalation and further Russian aggression and then maybe change that calculation in Moscow, where Putin concludes he can't use military force. He has got to go and seek a negotiated settlement.

GWEN IFILL: So you're suggesting that the U.S. provide weapons that they can use defensively, not offensively?

STEVEN PIFER: The weapons — first of all, the group that I was with when we proposed additional military assistance, the bulk of that is actually non-lethal assistance.

The one area that we visited in Ukraine three weeks ago, we found a real need was for light anti-armor weapons. The Ukrainians have stocks that are over 20 years old and almost three-quarters of them just don't work. And as was mentioned in the report, you have seen in December and January a significant influx of Russian tanks and other armored vehicles from Russia into Eastern Ukraine.

GWEN IFILL: John Mearsheimer, have we reached that point where that's the next step?

JOHN MEARSHEIMER, University of Chicago: No, I think it would be a fundamentally foolish idea to arm the Ukrainians.

And I think that for two reasons. First of all, it just wouldn't work militarily. The Russians can just counterescalate and they can balance any increase in weapons that we give to Kiev. So we gain no military advantage. And if you're talking about driving up the costs for the Russian, you're also going to drive up the costs for the Ukrainians.

There's going to be a real escalation spiral that sets in, and in effect you're going to be backing the Russians into the corner. And the question you want to ask yourself is, do you want to take a country that has thousands of nuclear warheads and back it into a corner? Do you want to raise the costs and risks for that country to the point where it might think about rattling its nuclear saber?

I think the answer is categorically no. I think the last thing that we want to do is try and solve this one militarily. What we want to do is solve it diplomatically.

GWEN IFILL: Professor, you used the term escalation spiral. Given the bloodshed of the last several weeks, hasn't that already done and is humanitarian aid enough to stop that?

JOHN MEARSHEIMER: It has begun, there's no question about that. But the point is, it could get a lot worse. What we're talking about here is upping the ante, having an arms race in Ukraine.

And the end result is the intensity of the conflict will spiral. And what I'm saying to you is, if it does work to Russia's disadvantage, if Russia is backed into a corner and the Russians become desperate, because core strategic interests are at stake — remember, we're talking about Ukraine here, which is right on their border — their incentives to pursue risky policies, which could mean nuclear weapons, are significant.

We just want to avoid that situation.

GWEN IFILL: Steven Pifer, what about this idea that you're just backing Russia into a corner and you're getting into a war we don't want to get into?

STEVEN PIFER: Well, first of all, let's be clear. The Russians put themselves in this situation. It's been Russian aggression against Ukraine that goes back to last March, beginning with the seizure of Crimea, Russian support for the separatists in Eastern Ukraine.

In June, you saw an influx of heavy weapons, including, apparently, the surface-to-air missile system that shot down Malaysia Air 17. And then Russian army units went in, in August. So, there has been a continual pattern of Russian escalation, even after September 5, when there was a cease-fire agreed.

If you look at the map in Ukraine, you will see that today the Russians and the separatists occupy about 500 square kilometers more than they did five months ago. So the Russians have been escalating. I would argue that you can put the Russians in the dilemma on escalation, where further escalation likely then, as Mr. — Professor Mearsheimer described, would involve the Russian army in a way that does two things.

One, it exposes at home for Vladimir Putin that the Russian army is fighting in Eastern Ukraine and it then raises the question of casualties. I don't think Mr. Putin cares about dead Russian soldiers, but he cares about the impact of that on his approval rating.

And it also then makes clear to Europe that the Russians are fighting there. So the idea that the Russians are automatically going to jump up I think is a mistake. One last point too is we talk about this in kind of a West-Russia context. Ukraine gets a vote.

I mean, Ukraine very much has a say or should have a say in how it's going to develop as a country.

GWEN IFILL: Professor Mearsheimer, assuming that you disagree with a lot of that, which I'm assuming you do, I do want to move you forward to what the other solution is. Is it diplomacy? Is it standing in place?

JOHN MEARSHEIMER: Just before I answer that question, Gwen, let me just say I don't think that Putin and the Russians were generally responsible for this crisis.

I think the West is, especially the United States, and it's NATO expansion that's the taproot of this problem. The fact that we have been pushing NATO and the E.U. eastward and trying to pull Ukraine out of Russia's orbit and make Ukraine a bulwark of the West right on Russia's border is what has precipitated this crisis.

GWEN IFILL: And what…

JOHN MEARSHEIMER: What we're doing is it exacerbating it by arming the Ukrainians.

GWEN IFILL: OK. But nobody has been armed yet, at least not lethal aid. What would diplomacy look like? What would Hollande-Merkel solution look like?

JOHN MEARSHEIMER: Well, I think there is actually a very simple solution to this problem, and that is to turn Ukraine into a neutral buffer state.

What the West has to do is explicitly take NATO and E.U. expansion off the table and make it clear to Moscow that the United States and its European allies have no intention of siding with a government in Kiev that is anti-Russian and pro-Western.

What we want is a neutral government. And then we ought to work with the Russians and with the IMF and with the E.U. to come up with some sort of economic package that can put Ukraine back on its feet. The fact is that the Russians have a vested interest in having a viable, but neutral Ukraine on their border. So there's no reason we can't work with the Russians to put Ukraine back on its feet.

GWEN IFILL: Steven Pifer, given what we saw happen with Crimea, it is possible, is there a reasonable fear that the Eastern Ukraine would become a breakaway state if this were to happen?

STEVEN PIFER: Well, I think what you see right now is the Russians are using Eastern Ukraine by sewing instability, chaos there. They're trying to destabilize the government in Kiev.

I think just a couple points to what Professor Mearsheimer just said. First of all, on the question of NATO, there has been zero enthusiasm in NATO for the last six years to enlarge to Ukraine. The Obama administration has never pursued it. And the Russians know this. I think that's simply a false argument.

The second point, though, is, again, when we start talking about pushing Ukraine back towards Russia, we're talking kind of spheres of influence. It's really kind of 19th century. And Europe was trying to move beyond that. And a fundamental point here is with the 1975 Helsinki Final Act, that was designed to say, Europe will play by rules.

And one of the cardinal rules was nonviability of borders and you don't use military force to take territory from other countries. That's what Russia is doing.

GWEN IFILL: Well, we will see what happens with the big meeting in Moscow the next few days, and we will revisit this.

Thank you both very much, John Mearsheimer in Chicago and Steven Pifer here with me in Washington.

STEVEN PIFER: Thank you.

JOHN MEARSHEIMER: You're welcome.