Twenty bucks says Russia will think any such base is against Russia, and will goose the arms race up again. Not that I'm against building the base, just an observation. It will definitely be received badly by the cold war dinosaurs.
See the problem is that the Cold War never really ended, and was just "frozen" for a short while during the nineties. US vs rest of the world rivalry (including Russia) will definitely deepen in the years to come. Russia makes no mistake which side Poland will be on in that race. Especially after Ukrainian elections, when Kremlin propagandists nominated Poland as their official "training bag".