PITTSFIELD -- Employees of a firm that produces body armor for American soldiers are doing important work in defense of the country, U.S. Sen. Edward M. Kennedy said during a visit to the company yesterday. Kennedy, a leading Democratic critic of the war in Iraq, visited Protech Armored Products, which in the last year has grown substantially to fill $40 million in orders from the Pentagon for protective armor plates used by soldiers as inserts. He stayed for more than an hour, meeting privately with company officials, touring the plant and then addressing employees. "It's an honor to be here,...