Brussels (AFP) – US President Joe Biden will travel to a town near the Polish-Ukrainian border Friday, trying to signal Western resolve against a Russian invasion that has increasingly turned to a grinding war of attrition. Air Force One will jet into the eastern Polish town of Rzeszow — bringing the US president less than 80 kilometres (50 miles) from a war-torn nation still struggling to repel a brutal Russian invasion. The trip is designed to underscore Washington’s willingness to defend NATO allies, as fears rise that the month-old war in Ukraine could spill westward sparking what the US …