When it's a choice between existence and annihilation it's not so difficult a choice.

For example, Finland has a program that will mine the entire border with Russia in just hours if Russia invades.

Placing mines on your own border for defense purposes is one thing. Doing an aggression in an independent country, placing mines there is completely different.

My gut feeling says that landmines can be more acceptable when placed in designated areas, for example a strip along the border with proper fencing. And maybe electronics to disable them when they are no longer necessary so they can be safely removed. This is a fundamentally different type of weapon than something that is hidden and anyone can inadvertently step/drive into.

And if it is correctly mapped and the map is well managed, then it is not quite as catastrophic as warlords simply burying mines somewhere indiscriminately.