If you're a democratic follower of democracy, be sure to bring the mortar sentry to bugs! Mortar sentries get distracted really easily by the closest target, so all of the pouncers, hunters, stalkers, chargers, commanders, and basically anything that isn't a hive guard will be sure to attract the mortar's attention and get your teammates killed. For maximum impact, be sure to throw the mortar a few meters behind you, since it can't deliver democracy within 10 or so meters of itself.

Sadly, the illuminates don't practically teleport to you like pouncers, so you won't get as many teamkills. However, the mortar sentry easily makes up for this shortcoming by being really really good against the two biggest illuminate threats: elevated overseers and harvesters. It's very democratic when you bring the (really awesome) mortar sentry and kill many undemocratic overseers and harvesters, so please do it!

While the other two suggestions are rarely used and heavily underrated by fellow helldivers for some reason, it's really meta to bring mortars to these so all of your teammates who dare to stand on the walls will blow up in explosions of death. This is so effective, in fact, that it even works well on bots because berserkers love silently chilling under walls to act as landmines for unsuspecting teammates. Don't think the limited range will save them either, because everyone is spread out so much you can't all be within the safe zone of the mortar.

Don't bring mortars to bots, especially against fortresses. Our poor bot bases would get wrecked if you brought the mortar, so please democratically refrain from doing so. You wouldn't get any teamkills for this either, because your teammates aren't standing in the base.

Don't use mortars at extract. Your teammates are all standing around it, and since it has a minimum range it can't hit them now, can it? Instead, bring tesla towers and incendiary mines to throw on extract. That'll net you lots of democratic teamkills!

Don't utilize pinging to control the mortar sentry's fire, except in cases where there's a beserker attacking your teammate. You'll be sure to net a teamkill then!

This has been Liberty Mann, and I am definitely not a bot. But if I were, I would be a very democratic bot.