Transcript for The strike on Syria's Shayrat air base

on a very busy Friday night. We're getting a much clearer picture of what led to president trump's order to take military action against Syria. Last night, the missile strike against Syria, more than 50 tomahawk missiles fired. Just two days after the attack, so many children among the victims. Officials say they have proof was a seyrian fighter jet that took off from there. And now, word that Syrian planes are taking off from that airfield all over again. Here's Martha Raddatz, leading us off. Reporter: Under the cover of darkness, dozens of U.S. Tomahawk cruise missiles fired into Syria from two Navy warships in the mediterranean. Raining down on the shayrat airbase, where the Syrian plane carrying those chemical weapons had taken off. The cruise missiles already launched as the president was wrapping up his first dinner with the Chinese president at mar-a-lago. Hours earlier, aboard air force one, president trump had signaled to the world that military action against Syria was a strong possibility. I think what happened in Syria is a disgrace to humanity. And he's there, and I guess he's running things. So something should happen. Reporter: Soon after landing in Florida, the president would give his commanders the green light. The Pentagon using military channels to let the Russians know, this was not an attack on their troops and aircraft in Syria. But did the Russians then warn the Syrian forces? Witnesses claiming they quickly moved equipment and personnel ahead of the attack. Syrian television showing what it said was the U.S. Assault in the distance. Syrian officials claiming at least seven were struck. The Pentagon says it struck all 59 of its targets. Destroying at least 20 Syrian aircraft, air defense systems, radar and ammunition supply bunkers. Once those missiles fell, the president huddled with his national security team to assess the damage. The retaliation coming just 60 hours after the world saw the first horrific images of that chemical attack, images that pushed the president to act. Tonight, I ordered a targeted military strike on the airfield in Syria from where the chemical attack was launched. Reporter: The Pentagon providing evidence it says shows Assad was behind the war crime. The flight path data of the Syrian warplane. And tonight, the U.S. Military looking into whether the Russians knew about that chemical attack or assisted in any way. Today at the united nations, ambassador Nikki Haley warned that the U.S. Could strike again. The United States took a very measured step last night. We are prepared to do more. So let's bring in Martha, live in Washington. We're learning tonight as we come on that the Russians have suspended the hotline that had been set up between the Russians and Pentagon? Reporter: The hotline was set up to deconflict the aircraft flying missions over Syria, so they don't run into each other. But there are radars and other backup. But another sign, the Russians are not happy with the American attacks on Syria. Martha, thank you. The white house saying this was a carefully targeted strike, aimed to send a clear message. I want to bring in Steven ganyard, 59 tomahawk missiles were launched from the mediterranean, and guided by advanced navigation systems to avoid detection? Yes, the missiles drop down low, they flew for somewhere between 30 minutes and an hour. And probably came ashore over Lebanon to avoid some of the surface to air missile systems, and went north, went after 59 carefully picked targets around the Fairfield. Take us deeper into the military choice they took here. President Obama considered military action after the chemical attack in 2013. The Pentagon offered president trump several choices. Go with a large strike or something very focused that would send a message. He knew he would not overthrow Assad, but was making a very clear statement, stop gassing your people, or we'll be back in a big way. Thank you. And this evening, we're also learning who was in the war room

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