It's worth pointing out: unlike Ukraine, Russia / the US are not signatories to the Ottawa Treaty on Land Mines - ie Putin can get away with this in Russia, but in much of the world this alone would be evidence of something like a warcrime on Russia's part
Landmines don't discriminate who they kill - if you're a soldier, even if you're drafted, you're to some extent you are expected to get into situations where your legs are blown off or whatever.
But who *isn't* expected is a child, 50-75 years from now, who just happens to be born in a village in ukraine, to have *their* limbs blown off by a landmine for a war that ended decades before they were born. *That* is why they are a prohibited weapon.