What with the Russian president all willy-nilly and , and the American president just as soon as he , NATO figured this was a good time to remind everyone how to stop a tank that just so happens to be rolling through your backyard.

Thanks, NATO!

American and Canadian army engineers showed how to stop a tank using a method called an “,” during a recent exercise in Lithuania, which borders Russia. The use of an abatis is thought to date back to the Roman Empire, and since then it’s primarily served as an anti-personnel defensive device. Knock down a whole bunch of trees with their sharpened branches facing outwards, and all of a sudden you have a pretty effective defensive structure.

But if you make an abatis out of a massive, tangled web of whole trees, you can stop a lot more than just enemy infantry. You can slow down an entire column of tanks.

Of course, there are ways around it. Mostly, you could just drive around it, if there’s another route or the surrounding forest isn’t too thick. And you can also just get rid of it by burning everything in sight. That’s why most defensive positions these days are made out of other materials, like twisted metal and wire.

If all you’ve got is some explosives, some chainsaws, and some trees, however, an abatis will do.

You know, just in case.