I’ve written columns about Iran’s awful economic policy.

I’ve written columns about Japanese economic challenges.

And I’ve written columns about Poland’s recovery from communism.

So let’s look at a chart comparing changes in per-capita GDP in all three nations over the past 30-plus years.

What you’re seeing in a story of both convergence (Poland catching up to Japan) and divergence (Poland leaving Iran far behind).

Convergence is normal. Poor countries should grow faster than rich countries.

When there’s divergence, however, the cause is almost always bad-to-horrible economic policy in the country that is lagging. And since Iran is one of the five-worst nations for economic policy, it’s hardly a surprise that there’s been very little growth (and the recent conflict may cause the numbers to get worse).

P.S. It’s not as if Poland is a superstar country. It ranks #40 in the latest Index of Economic Freedom and only #76 in the latest Economic Freedom of the World.

P.P.S. Japan’s economic policy is not bad. Indeed, it ranks as being freer than Poland. But the trend is not positive and it’s demographic problems have already materialized (while Poland’s demographic problem is just beginning).