President Park Geun-hye called Thursday for high military preparedness as she paid a visit to troops conducting joint exercises with the United States, saying war should first be prevented, but must be won if it were to break out. \"The military should prevent war in advance based on strong deterrence, but if war breaks out, we must win,\" Park said during an unidentified site of the Ulchi Freedom Guardian (UFG) drills that kicked off Monday for a 12-day run.