He was active in the provincial defense, and commanded a regiment in the 1710 siege of Port Royal, the capital of French Acadia, during Queen Anne's War. He was responsible for overseeing the defenses of Boston in the 1720s, and was sent to negotiate with the Iroquois and Abenaki during Dummer's War. Jonathan Belcher, initially a political opponent, later became an ally, and selected him to serve as his lieutenant governor in 1730. Tailer held the post until his death, and was interred in the tomb of his uncle, William Stoughton.