It's getting tougher and tougher to be shocked by our politics these days. But if there's one stat that should shock you, it's this one spotlighted by James Hohmann in Tuesday's Daily 202:

  • In 2013, when the Syrian government used chemical weapons on its own people, just 22 percent of Republicans supported U.S. missile strikes in retaliation.
  • Last week, the Syrian government allegedly used chemical weapons on its own people, and 86 percent of Republicans support U.S. missile strikes in retaliation.

Here's how that remarkable political evolution looks:

The stat comes courtesy of our new Washington Post-ABC News poll, which tested reactions to President Trump's strikes last week and also tested views back in 2013, when President Barack Obama was considering doing the same. (Democrats, for what it's worth, experienced no such evolution, with 38 percent supporting strikes in 2013 and 37 percent supporting them today.)

So what accounts for the difference for Republicans? The 2013 chemical weapons attack was actually deadlier, so it's not as though this one was unprecedented. Perhaps Republicans decided a more serious response was now warranted, given that the United States didn't wind up retaliating in 2013 — and given that Syria did it again after failing to turn over all of its chemical weapons stockpile, as it promised to in a 2013 deal.

These are indeed the most charitable conclusions you can draw for the GOP's complete 180.

Much more likely, though, is that it has just about everything to do with partisanship and the man in charge not being named Obama. Here's why.

There was actually another Washington Post-ABC News poll that tested views of what the United States should do in response to Syria using chemical weapons. It came in December 2012before the 2013 chemical weapons attack. It was a hypothetical.

The question: “What if the Syrian government uses chemical weapons against its people? In that case would you support or oppose U.S. military involvement in Syria?”

In response to this question, fully 67 percent of Republicans said they would support military involvement.

So 67 percent of Republicans favored military action if Syria used chemical weapons. Nine months later, it happened and Obama asked for congressional authorization for missile strikes, and just 22 percent of Republicans supported it. Then, four years later, Syria used chemical weapons again and Trump struck without congressional approval, and 86 percent of Republicans gave him the thumbs-up.

Democrats have often accused Republicans of obstructing everything Obama did for no other reason than that it was Obama doing it. I'll confess here that I think that often oversimplified things and that there were plenty of legitimate ideological differences.

But at least on one issue, it's pretty clear what happened. Republicans wanted action when Obama didn't, then they didn't when he did. And now that their guy's in charge, they're even more gung-ho than they were in 2012.

Yay, blind partisanship.