Donald Trump - each week I think I'm not going to talk about him for a while, and then he does something prattish again, and I can't help myself.

He's losing his appeal with women. Lord knows how he ever had any, given the long list of sexist and misogynistic comments that seem to fall from his mouth daily. But in the latest polls, fewer women are backing him.

And so when that happens, what do you do? You roll out the wife. Your glamorous wife, Melania Trump.

And on stage, Melania defended her husband. She said, "No matter who you are, a man or a woman, he treats everyone equal."


She neglected to mention, of course, a caveat to that. If you're Mexican or Muslim then Trump absolutely won't consider you his equal. And she went on to say "As you may know by now, when you attack him, he will punch back 10 times harder."

I'm not sure that's what you really want to hear from a wife, is it?

Anyway, it's the Wisconson primary today and Trump has gone back to spouting off about what has delighted his voter base in the past - and that's wading into Mexicans again.

He's back talking about the wall that he's going to build between America and Mexico.

He came up with this grand idea but he's never revealed how it will be funded - well he's said Mexico will pay for it, but how? The wall is going to cost up to $US10billion to build.

He now says he will stop Mexicans deemed to be living illegally in America from sending money home. He'll change the law.

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Apparently Mexicans send over $US24 billion dollars into Mexico every year. That's more than Mexico generates from its oil revenues.

So Trump will stop that, and he says he'll cancel some Mexican visas, and he'll put up visa fees and impose some hefty tariffs on imports too.

And by economically crushing Mexico, he'll force the Mexican government to build the wall - and once the wall is built - he'll ease back on some of those tariffs.

I think he's got this wrong. Even in America, surely, you don't want to be responsible for crushing another country. The impact of shutting down billions of dollars of revenue, the impact on the country's infrastructure, and health system.

As I said, I think he's got this wrong, but we'll see today in Wisconsin.

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