When it comes to economics, Donald Trump is a big protectionist, while his fellow Republican presidential candidate Ted Cruz is a devotee of the gold standard. And we know quite a lot about what their policies would do.

Protectionism makes economies less efficient, but it does not, in general, destroy jobs. Put a tariff on imports and people will spend less on imports - but they will likely spend more on other things instead. So, as I mentioned, a worldwide turn toward protectionism would both reduce countries’ exports and reduce their imports, with the overall effect on spending and, hence, on employment, more or less a wash.

I’m aware that Moody’s Analytics recently released a study claiming that “Trumponomics” would be a huge job destroyer, but I really don’t understand how it got that result. My best guess is that the analysts are assuming that former spending on imports just goes away, which is not a good assumption to make.

And no, protectionism didn’t cause the Great Depression. It was a consequence, not a cause - and much less severe in countries that had the good sense to drop the gold standard. 

Which brings us to Mr. Cruz, who is enthusiastic about the gold standard - which did indeed play a major role in spreading the Depression.

First of all, the problem with gold is that it removes flexibility. Given an adverse shock to demand, it rules out any offsetting loosening of monetary policy.

Worse, relying on gold can easily have the effect of forcing a tightening of monetary policy at precisely the wrong moment. In a crisis, people get worried about banks and seek cash, which increases demand on the monetary base - but you can’t expand the monetary base to meet this demand because it’s tied to gold. On top of that, a slump drives interest rates down, increasing the demand for real assets that are perceived by people as being safe - like gold - which is why gold prices rose after the 2008 financial crisis. But if you’re on the gold standard, nominal gold prices can’t rise - the only way real prices can rise is through a fall in the price of everything else. Hello, deflation!

So on economics, again, Mr. Trump is ignorant and unpredictable - but Mr. Cruz knows what isn’t so, and his policies would lead to predictably dire results.