The first group of the 2,000 American troops taking part in a big three-week joint war game with the Israeli army landed at Ashdod port Tuesday. US Patriots are due for delivery soon. The live-fire exercise beginning Oct. 21 will simulate a missile attack on Israel with the Patriots and the Israeli Arrow and Iron Dome anti-missile batteries taking part. It coincides with a high alert on Israel’s northern borders with Syria and Lebanon. The Chairman of the Joint US Chiefs of Staff, Gen. Martin Dempsey will be present for part of the war game.