NATO will begin the largest air-force-deployment exercise in Europe in the alliance's history on June 12 in a display of unity toward partners and potential threats such as Russia. The German-led Air Defender 23 will run until June 23 and include some 250 military aircraft from 25 NATO and partner countries including Japan and Sweden, which is bidding to join the alliance. Up to 10,000 personnel will participate in the drills intended to boost interoperability and preparedness to protect against drones and cruise missiles in the case of an attack on cities, airports, or sea ports within NATO territory.