Transcript for Democratic Party is 'careening to the left': Rep. Seth Moulton
Today we come together as one nation with this very special salute to America. We celebrate our history, our people, and the heroes who proudly defend our flag, the brave men and women of the United States military. The president stuck to his message on July 4th. Using his speech at the Lincoln memorial to honor American history and showcase American military might. A few days later, I sat down with congressman Seth Moulton one of the military veterans in the 2020 democratic primary, who took issue with the president's speech. Moulton hasn't registered in the polls yet. I asked him, what's keeping him in this race? We started with his reaction to the president's salute to America. I think trump by saluting the troops, includes saluting the flag -- his unwillingness to answer the call to go to Vietnam. His unwillingness to confront Putin. That's what real service to the country is, is making a sacrifice to do the right thing for others and are trump doesn't understand that at all. Reporter: But president trump used that speech to call others to service. To the young Americans across our country, now is your chance to join our military and make a truly great statement in life and you should do it. Quite something coming from someone who refused to do it himself. Do you give the president any room to say he's grown, he's grown to appreciate the military, he's learned from whatever he did in the past? I'd love to be able to say that about the president because it would be good for America. But if that were true, he would act presidential in conducting our foreign policy. He wouldn't continue to put our troops at risk by threatening war with Iran, by failing to stand up Russia. We need a commander-in-chief who does the right thing for the country. He's not keeping America safe. Which is something that I have spent a majority of my career doing. I'm sure if he was sitting here, he'd say, look, north Korea isn't testing nuclear weapons right now, they're not shooting off ballistic missiles right now -- North Korea continues to refine nuclear material. They have more now than at the beginning of the presidency. We're not near a sort of an agreement. Reporter: I first met Seth Moulton in 2007 at his parents' home in marble head, Massachusetts, as the Harvard graduate was heading back to Iraq for his fourth combat tour. I think a lot of people look at me and say, why do you want to go back now, be a part of the war when it's going so poorly? I think is this is the most important time for people to serve. Reporter: While home in Massachusetts, Moulton helped his interpreter with his effort seeking asylum in the U.S. Did he get asylum? He did. He did, he's one of the many people who came to America looking for asylum, a perfectly legal thing to do which I think is lost in this immigration debate today. He's an American hero, too, he put his life on the line not only for his country Iraq but for his new country America. Reporter: Those strong feelings and that sense of service is what drives the 40-year-old Moulton to run for president today. You got to stand up for your country and fight for its values when they're most under threat. That's why I went back to Iraq. As much as I disagreed with the war, I could have influence how it was fought every single day than just by being back home. Reporter: On the campaign trail, Moulton has opened up about his PTSD and seeking help. Recognizing healthcare is a top issue for voters. He differs with the Democrats in the race calling for universal government insurance. The bottom line is, everybody in America needs healthcare because it's a human right. We should get there by doing what Obama wanted from the beginning. Like a public option, medicare if you'd like it, that competes against private healthcare plans. You have options, you have choices that competition will bring down prices, bring down prescription drug prices for everybody. You talked about Bernie Sanders and compared it, it's not really alike, is that a fair I think it's a fair comparison. And, what you saw on the debate stage was Democrats careening to the left promising a bunch of free things without a real strategy for getting these thing done for Americans. Reporter: Moulton didn't have a chance to make his pitch to voters on the debate stage and he's unlikely to qualify for the second debate, but he had this advice for his fellow candidates. I do think trump is going to be harder to beat than many Democrats like to believe. If we spend our time rehashing votes from four years ago in congress, rather than realistic plans to achieve our goals, I think it's going to be a really tough election for us. That's why I'm running a campaign based on service, on reclaiming patriotism from right-wing politicians who think they own it. On what it means from a democratic perspective to keep America strong and safe. Reporter: While it's not reflected in many polls yet, Moulton believes his message is resonating with voters, and he's not ready to give up the fight. People are excited to hear a different perspective, and a different view of how we can build the coalition that we need to beat Donald Trump and bring the country together to actually accomplish the things that we'd like to do, not just in 2020 with winning but in 2021 with leading the country. So you're staying in? Absolutely. I've been in tough fights before. I'm going to keep going. Our thanks to congressman Moulton.
This transcript has been automatically generated and may not be 100% accurate.