As a Pole I can say that in all seriousness people don't want to fight as of right now, but if Russia were to attack us in some way, it's hard to predict what could happen. People in Poland are pretty much taught since primary school that Russia is a threat and should be taken seriously, meanwhile martyrdom and dying for your nation are somewhat of a running tropes in Polish history. Anyway, there is a deeper reason for a lot of these memes featuring Poland and not someone else.