By Simon Gardner BUENAVISTA, Mexico (Reuters) – Clutching shotguns, rifles and battered submachine guns, dozens of vigilantes prepare to head out on patrol in this rugged corner of restive western Mexico, where they are at war with a drug cartel. Moments later, an armored convoy of federal police passes by. In violence-racked Michoacan, an impoverished agricultural state about 1-1/2 times the size of Switzerland, vigilantes are battling a cartel called the Caballeros Templarios, or Knights Templar, for control of swathes of the failing state. After letting the conflict brew, the government this month vowed to assert control but its messages have been contradictory.