After the decision to move American Ballistic Missile Defense from Poland to the sea, the Poles (especially the leaders who invested a lot of political capital in making the sale to their own people) have felt slighted. Is it possible the US doesn't really care about Poland? If the Russians ratchet up the pressure--which they will, it's built into the geopolitics of the situation--will the US be willing to take some risks to serve as a counter?
That's the real issue behind the announcement to station American troops and a battery of Patriot missiles on the soil of Poland. One missile battery won't have much real effect, and the troops will be on rotation from Germany, but the symbolic message is there. Yet another "tripwire." Since Russia and Belarus recently held nuclear war games, including a simulated beach landing in Poland, some Poles are happy to get whatever support they can.