KYIV, Ukraine — Polish Foreign Minister Radoslaw Sikorski sat for an interview with me at Poland’s Embassy in Kyiv this week. Sikorski had arrived in Ukraine as Russia was pushing the war closer to his country.

Russia has intensified strikes on the Ukrainian side of the Polish border, increasingly targeting the railways, roads, and crossings connecting Ukraine to the rest of Europe. Last Sunday, a Russian drone struck a Kyiv-Warsaw passenger train at a station roughly 1.5 miles from Poland. A diplomatic train carrying former British Prime Minister Boris Johnson, former Swedish Prime Minister Carl Bildt, and European security officials had passed through shortly before the attack, and former CIA Director David Petraeus was still at the station aboard another train. By Friday, Polish officials said Russia had attacked four Ukrainian border crossings in a week.