Transcript for Diane Sawyer Interviews President Obama
we come on the air tonight a big development in the u.S. Action in syria. Is a teal now possible? Did the russian's persuade assad to turn over his chemical weapons. Moments ago I sat down with president obama who seemed to be signaling the tough stand by the u.S. May have caused a dictator to back down. If bashar al-assad used control of his chemical weapons to international authority, are we back from the brink? Is military strike on pause? Absolutely. If, in fact, that happened. I don't think that we would have gotten to this point unless we had maintained a credible possibility of a military strike and I don't think now is the time for us to let up on that. I want to make sure that that norm against use of chemical weapons is maintained. That's in our national security interest. If we can do that without a military strike, that's overwhelmingly my preference. Now the key is can we see is there a sense of urgency. Urgency meaning a week, a month? This is one of the situations where the stakes are high but they're long term. They're not immediate but they're serious. I don't anticipate that you would see a succession of votes this week or any time in the immediate future and so I think there will be time during the course of the debates here in the united states for the international community, the russians, the syrians to see if we can resolve this. Weeks? I'm not going to put a particular time frame on. We know what's at stake here. We know that the international community, even assad's allies like iran agree that chemical weapons use is abore achbt. You still want congress to vote authorization and you still reserve the right to strike if they say no? Strikes may be less effective if I don't have congressional support and if the american people don't recognize why we're doing this. So I haven't made a final determination in terms of what next steps would be. My hope would be that I can persuade congress that this is important. My hope is that I can persuade some of the american people that this is important. But ultimately I understand why a lot of americans are resistant. I think the polls are clear. I read them. This is not iraq. This is not afghanistan. This is not libya. The goal would be to degrade the capacity of assad to carry out the specific chemical weapons attacks. Bashar al-assad has said everything is possible in terms of retaliation. Expect everything. Expect everything. Do you feel at this moment looking at everything that's possible that the american people should brace for retaliation? No. Look, we take all precautions, but understand, assad's capabities are not significant compared to ours. They're significant compared to an opposition that are not professional fighters. They have allies? They're significant relative to 400 children that they gassed. They're not significant relative to us. Iran is not going to war with the united states over the use of weapons that they, themselves, october to. But I think it is important for us to understand that if, in fact, the choices between a world in which dictators and other countries start believing it's acceptable to use chemical weapons on children, that will make it more dangerous for us. Our troops when they're in theatre all having to wear gas masks because they don't know whether chemical weapons will be used. If they can resolve this without military intervention that's my great preference. I would much rather talk about how we can provide early childhood education to our kids, create more jobs, and focus on all the things that I think the american people care deeply about. But my responsibility as commander in chief is to make sure I think about the long term safety and the use of chemical weapons. Thank you, mr. President. Thank you, diane. White house correspondent jonathan karl and martha raddatz both here. Martha, what a turn of events today. Someone said it's whiplash today. It's absolute whiplash. For the president to say this is a potentially positive development that may deter military strikes, put them off, saying to you absolutely it could put off military strikes, but when you look at it, his goal all along has been to deter any future chemical attacks in syria. If he can get some sort of break through here with syria, they don't have to strike. And they're going to stay on alert nonetheless. Military forces are ready to go whenever the president gives the order, but we have to see if congress votes on that to begin with. What about that jonathan karl? It looks as if congress is going to have a long time to decide now. The senate just announced a few minutes ago that they're going to delay the vote. It looks really bad for the president, especially in the house. They need 217 votes in the house to pass. That's the imagimagic number. Look where our vote count puts it. Only 44 have said yes. 241 members of the house saying they're either no or leaning no. This looks really tough. The white house still believes they could turn this around. You had 70 members of the congress down to the white house today. The president is going to meet with all 100 senators tomorrow. This russian development, a lot of members I'm hearing from are saying they hope this is a way out. the moment anyway to look and see what the developments bring. Thank you, jon, thank you martha. The president is going to speak to the nation tomorrow night and abc news will be carrying it live.
This transcript has been automatically generated and may not be 100% accurate.