Transcript for Experts break down historic meeting between Biden and Putin
department spokesperson Sarah izger. Sarah, this is your first night on "Nightline," we're honored to have you. Rahm, Joe Biden has called Vladimir Putin a worthy adversary. How did Biden do today? Well, first of all, I think you have to put the trip within the context of the whole week. And I think it was a very good week for the president. And it made Americans feel good about themselves. Domestically it was very good. I think our relationships, it was very good. He got nato to endorse a series of things that he had been pushing, showing again that America can lead the coalition on both Russia, China, and other issues. I think sitting with Putin, I think the biggest thing I would say today that was very important is he -- I'm surprised nobody followed up on this. Here are the 16 things that if you touch these sectors in a cyber attack, you will have a response. He drew red lines around a cyber attack. That had never really been done yet by a president of the united States. Sarah, certainly muscular words from the president today. Who do you think won, or can each side claim progress? Vladimir Putin wants to be considered an equal of the United States and China. So getting to sit down with a president of the United States, as he's gotten to do with past presidents as well, that is his win. That's all he needs. Biden, unfortunately for him, has a much, much higher bar to claim a win. You know, as Rahm said, he can talk tough, he can set these red but all that's doing is setting up what will Biden do the next time there's a cyber attack? And there will be a next time. Rahm, Putin said he saw some, quote, glimmer of trust today. A lot of American presidents have met with Putin, some making progress, others not. Do you see any glimmers of trust Ater today? I would not measure this by a singular meeting, I would measure this of what comes out of the meeting, working groups, et cetera. Again, Sarah's right, there will be another attack. The real measure will be about a year from now, we'll know whether there are glimmers of hope, levels of trust. I think the main thing to be honest, Putin now has a predictable, seasoned political team. He can't do -- run circles around like he did around Donald Trump, as you saw in Helsinki. To me the measure of this will be a year from now when we look in the rear-view mirror, this was the beginning of something different. Sarah, in talking about these cyber attacks, the president put down a red line. Do you think that it's something that Putin will honor, or as you said, it's his style to always kind of push the envelope? No, I do not Putin will honor that. He is testing Biden. And the question will be, does Biden do more than what president trump did? It's interesting, if you look back at the trump years, trump's rhetoric was very pro-russia, putin-friendly. But what the trump administration actually did was they sanctioned Russia over and over again, they had statements of condemnation from the state department, the department of justice when I was there indicted 12 Russian intelligence officers for their election interference, for hacking the democratic national committee, Hillary Clinton's campaign. What is the Biden presidency, what is the Biden administration planning to do that is more than that, that will see results that the trump administration frankly didn't see? The way I would measure this, and I would take a look right now, is that they've met each other the first time. You've got 16 measures. If, in fact, Putin -- I don't believe Putin wants to be on the outside. The worst thing that happened was getting kicked out of the g8. The worst thing is also being seen as ostracized in Europe, seen as a dysfunctional force. He has major problems in Syria, got a problem with Turkey, being sucked into what's happening in Libya. He does want this acceptance, as Sarah noted, but it's not just a meeting. He didn't get everything out of it. He got the first step of, you can be an illegitimate player and seen around the world as somebody who kills people, ransom attacks, cyber attacks, et cetera. Or you can be part of the legitimate world countries and powers that are respected and also part of that system. The president puts real guardrails and told him, and the follow-through is going to be of this. Sarah, we'll close out tonight with you. While Putin likes to think Russia is a big player in the international scene, isn't China a much bigger threat and do you think Biden considers this a warmup for negotiations with China's president? I absolutely think that his team sees this as the opening gambit, a practice run, if you will. If you're in the "Rocky" movie, this is the guy rocky fights early on to see if he can beat him. China is the big adversary. XI has far more tricks up his sleeve and far more pieces he can move on this puzzle that are more dangerous and more adversarial to American interests than Putin. So how Biden is able to deal with Putin, a fairly one-dimensional player, will be the practice run for how he deals with XI, which is three-dimensional chess, absolutely. Putin has issues in Ukraine that Biden needs to deal with. That is frankly far, far easier than dealing with Taiwan, than dealing with the genocide that is happening with the uighurs, compared to Putin's human rights violations. So I hope that the Biden team got their sea legs under them this time, because there are much bigger things up ahead. Sarah, welcome to "Nightline." Thank you both for your time tonight.
This transcript has been automatically generated and may not be 100% accurate.