I'm not American and not the commentor, I'm observing from far away.
I agree, people should vote for the best possible candidate. Even single issue voters. The alternative is worse for this single issue. If I was American, I'd vote strategically like people on this thread are saying.
However
There are Americans that had friends, family members, and colleagues killed in this conflict, and they can't stomach going to the polls and voting for Biden after how he's acted throughout this conflict. I won't hold it against those people for not voting.
I can't even imagine what it would be like to have that happen and be told "go vote for him anyways". As true as it might be, it's not my place.