Donald Trump told an enthusiastic, cheering crowd in Michigan that US immigration laws were "corrupt" and that he would shut down the government in September if the $1.6 billion proposed for the border wall isn't appropriated.

The laws are so corrupt, they are so corrupt. One of the reasons they do it is because the Democrats actually feel and they are probably right, that all of these people pouring across are going to vote for Democrats. They will vote no matter what we do. So there is a theory they do it for that. They do it for a lot of reasons. A lot of times they don’t even know what they are doing or why they are doing it. But we have to have borders and we have to have them fast. We need security and we need the wall. And, again, that wall has started. We have $1.6 billion. We come up again September 28. If we don’t get border security we have no choice, we’ll close down the country because we need border security.”

Our immigration laws may be corrupt, but worse, they don't work. Worse still, they make a mockery of border security and our sovereignty.

Congress has a duty to reform the broken, ineffective immigration system but are stymied by extremists who either want to close the border entirely, or open it completely. As long as that's the reality, we will continue to limp along with the current system we have.

Trump's other big applause line during his speech was when he mentioned his North Korean diplomacy and the crowd began to chant "Nobel" as in the Nobel Peace Prize.

TRUMP: "So we have to renegotiate these deals. If you look at China, last year with China, and look, he’s been a great help. President XI is a friend of mine, but he likes China. I like the usa. But he’s a friend of mine. But you know what? He’s been a great help on the border with North Korea and a lot of good things are happening there. A lot of good things. I’m not going to give you what’s going to actually happen because we don’t really know. But I will tell you one thing, we’re not playing games. And I remember, you know, it was very rough three, four months ago — that’s very nice, thank you. That’s very nice. I just want to get the job done. So if we would have —

[AUDIENCE CHANTS 'NOBEL!']

TRUMP: "If we would have said where we are today from three or four months — months ago, do you remember what they were saying? He’s going to get us into nuclear war, they said. No, strength is going to keep us out of nuclear war, not going to get us in.

We're a long way from peace, but he's right. We're closer now than we were 4 months ago.