In 1898, when the United States bombarded and blockaded San Juan during the Spanish–American War, Barbosa and other doctors who lived in Bayamón traveled to the town of Cataño and took a ferry to the capital. Barbosa, as a member of the Red Cross, went to the aid of the wounded Puerto Rican and Spanish soldiers. He and his party on the ferry had to travel across San Juan Bay at risk, as they were under cannon fire. Barbosa and those with him were recommended by the Spanish government for the "Cruz de la Orden del Mérito Naval" (The Cross of the Order of Naval Merit) for their bravery.