Back on New Star, there is a debate over whether the U.S. should extend or walk away from the treaty.

So for that debate, we get two perspectives.

Rose Gottmiller was the chief U.S. negotiator for the New START Agreement during the Obama administration

and is now distinguished lecturer at Stanford University.

And Frank Miller had a 30-year career in government focusing on nuclear weapons

and national security. He's now a principal at the Skowcroft Group, an international consulting

firm. Thanks very much to you both. Welcome back to the NewsHour. Rose Gottmiller. Let me start with you.

You think the U.S. should continue to abide by the limits in New START. Why?

I think that the limits of New Star Treaty are important

because they keep not only the United States under limits, but they keep the Russians under limits

at a time when the Russians could move rather quickly to upload warheads and put more warheads on each of their missiles.

And therefore, I think, outrun us in this period when we are looking at China building up,

as Secretary Rubio quite rightly said, they are building up quickly.

So it's to my mind a no-brainer to keep the Russians under limits as we ponder and plan and prepare to

confront the Chinese on this matter. Frank Miller, is it a no-brainer to extend the treaty for one year?

Absolutely. No, absolutely not. Paradoxically, getting rid of the treaty makes us stronger,

makes the world more peaceful. The treaty capped U.S US force levels, deterrence force levels,

at the 2010-2011 levels.

The world is vastly different.

We now face an antagonistic Russia

and a growing antagonistic China.

And so if we are kept at deterrence levels

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