During a press conference alongside Polish President Andrzej Duda on Sept. 18, U.S. President Donald Trump confirmed that the White House was considering whether to open a permanent American military base in Poland. Warsaw, which requested the base, also sought to sweeten the pot by promising to contribute up to $2 billion for its construction. The move is part of a Polish strategy to develop close political, economic and military ties with the United States so as to prevent potential Russian aggression. It also happens at a time when Warsaw's relations with the European Union are turbulent due to disputes between Poland and the European Commission over the rule of law in the country; Warsaw, accordingly, wants to show it has friends in high places. But actually building the base might prove more difficult....