Administration allies say they are fed up with the Defense Department’s third-most senior leader and his foreign policy surprises. More than a half dozen diplomats interviewed in Washington and Europe also complain that the Pentagon’s once steady consultations have slowed as Colby’s office crafts that strategy, along with a review of troop locations worldwide.That uncertainty deepened after the Pentagon quietly decided not to replace a rotational Army brigade in Romania, Hungary and Slovakia — a move the Romanian government learned of only two days before it was announced, according to a U.S. defense official and a Romanian official.One NATO diplomat...