EXCLUSIVE: Recent Russian incursions into NATO airspace have sharpened divisions inside the alliance over how to respond, exposing both the strength and the limits of collective defense. DENMARK CONSIDERS TRIGGERING NATO ARTICLE 4 AFTER DRONES FLY OVER AIRPORTSA NATO spokesperson confirmed Rutte and Michal spoke Friday and said the secretary general "has supported Estonia throughout the process." Last month, missile-carrying Russian MiG-29s flew into Estonian territory, following an earlier breach of Polish airspace by 19 drones and repeated incursions over Romania. The Russian jets in Estonia were eventually escorted out of its territory by Italian F-35s. The debate cuts to a deeper question: what constitutes a "need" to shoot down Russian jets?