Transcript for Is the Summer of Trump Coming to an End?
a serious common ground.highway, H, ia sinflnse G eeth war, crossing the mediterranean Sean ims fy liboats, where so many have lost their lives, mang their way north into Europe. International outage exploding after thesare hetbreaking images of a 3-year-old toddler drowned on a tursh bkich.ea raising questions about how many refugees countries can and will take in. Will T en iuragcomoree to make th rie pe tlousp?ri but for these young Syrians those are questions for another day, right now, ey'rthe just happy they made it this far. Ready for a new life. And even av treling for days and walking so much, you're still happy. It's finished. Reporter: Your future starts now? Yeah. In the latest national poll. His highest grade yet. But it may be time for trump to hit the books, after he stumbled through foreign policy questions, in an interview with conservative radio host Hugh Hewitt. Are you familiar with general soleimani? Yes, but go ahead and tell me. He runs the quds forces. Yes, okay, right. Do you expect -- And I think the kurds have been hobblely mistreated -- No, not the kurds. The quds. Reporter: Trump later said he didn't hear the question, blasting Hewitt as a third-rate announcer with gotcha questions. He says he has plenty of time to study up. The difference between hezbollah and hamas doesn't matter to you yet -- It will when it's appropriate. I will know more about it than you know. Reporter: Will trump's fumble bring on revenge of the nerds? Bring in Marco Rubio, who's on the senate foreign relations committee. If you don't know the answers to those questions you won't be able to serve as commander in chief. Reporter: And Jeb bush gave trump a bilingual attack. Reporter: Now, another outsider is making a bid to be the most popular kid in class, Dr. Ben Carson making a huge leap in the polls, now second to trump nationally and tied with him in Iowa. A new contender on the rise, his opponents on the attack, so will the summer of trump be followed by the fall of trump? For "This week," Jonathan Karl, ABC news, Washington.
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