Romania’s foreign minister on Friday called Article 4 of NATO’s founding treaty “an instrument that Romania can use” after a drone, which officials said was Russian, crashed into an apartment building in the country. Article 4, which allows a NATO member to open formal discussions about threats to its security, has come under renewed focus since Russia invaded Ukraine in 2022, especially in the wake of multiple incursions by Russian drones and jets into NATO countries’ airspace. Oana Toiu,