At least they are doing it with American weapons. It’s a shame that they have to do it because they can’t rely on American support in the face of Russian aggression.
Warsaw wants to buy the Patriots because it is concerned about Moscow placing missiles in Kaliningrad that borders northern Poland, the BBC’s Adam Easton in Warsaw reports.
Poland currently has no defence against such weapons.
The missile deal – which could be worth about $7bn (£4.7bn) – is the largest in Polish history, our correspondent says.
It is part of Poland’s plans to spend $35bn to modernise its military over the next eight years.