Poland wants and relies on help from the EU, that includes Germany. A lot of polish people benefit from the schengen system and the ability to work abroad. However, Poland tries to opt out of a significant chunk of the shared burdens of the european union, and one of those burdens is that the european union does have an asylum policy that accepts people that are threatened in their _home_ country - not countries that they've been fleeing through. It's a legacy of the world wars and the nazi genocides which saw a lot of people incapable of fleeing because no country would accept them - and IMHO - the embodiment of one of the most important core value of the often proclaimed christian tradition: Compassion towards others in need.

Given that Poland happens to share a border with an aggressive empire (well, if you count the Kaliningrad enclave as sharing a border), I question the wisdom of opting out. If you're afraid of a war, I'd be more concerned about making friends than alienating them.