He's insisting Mexico will pay for the border wall — even if the administration is not sure how that will happen.

He thinks the U.S. should have taken Iraq's oil — which technically would break international law.

He really believes in sending someone in to fix Chicago's gun violence problem.

Yesterday, Trump signed an executive order to start the construction of the southern border wall. As has been previously reported , construction of the project will be financed initially with taxpayers' money. "All it is, is we'll be reimbursed at a later date from whatever transaction we make from Mexico. Now, I could wait a year and I could hold off the wall. But I wanna build the wall," Trump said. "We have to build the wall. We have to stop drugs from pouring in. We have to stop people from just pouring into our country. We have no idea where they're from. And I campaigned on the wall. And it's very important. But that wall will cost us nothing." When Muir pointed out that President Enrique Peña Nieto had said in recent days that Mexico wouldn't pay for the wall, Trump doubled down. "David, he has to say that. He has to say that," he insisted. "But I'm just telling you there will be a payment. It will be in a form, perhaps a complicated form. And you have to understand what I'm doing is good for the United States. It's also going to be good for Mexico." However, later in the evening, Peña Nieto repeated once again that the country will not finance Trump's project. "I'm saddened and am against the decision of the United States to continue with the construction of a wall that for years, far from joining us has divided us," he said in a video statement released on Wednesday night. "I have said time and time again, Mexico will not pay for any wall."During his speech at the CIA headquarters last Saturday, Trump said that perhaps the U.S. should have kept Iraq's oil after the war . When Muir asked about this statement, the president repeated his belief. "We should have taken the oil. You wouldn't have ISIS if we took the oil. Now I wasn't talking about it from the standpoint of ISIS because the way we got out was horrible. We created a vacuum, and ISIS formed," he said. "But had we taken the oil, something else would've very good happened. They would not have been able to fuel their rather unbelievable drive to destroy large portions of the world." Muir reminded Trump of the critics who are saying this would break international law. But the president didn't back down. "Wait, wait, can you believe that? Who are the critics who say that? Fools," Trump responded. "I don't call them critics. I call them fools."Earlier this week, the president sent a tweet alluding to the gun violence crisis in the city. He tweeted, "If Chicago doesn't fix the horrible "carnage" going on, 228 shootings in 2017 with 42 killings (up 24% from 2016), I will send in the Feds!" When asked by Muir what he meant by "sending in the Feds," Trump was vague in his answer but emphasised that he would send in "what we have to." "They're not doing the job. Now if they want help, I would love to help them. I will send in what we have to send in," he said. "Maybe they're not gonna have to be so politically correct. Maybe they're being overly political correct. Maybe there's something going on. But you can't have those killings going on in Chicago. Chicago is like a war zone." The only issue is that the city already has considerable federal support , and sending in reinforcements from the National Guard would be out of the question for Mayor Rahm Emmanuel.