Blockade of Puerto Rico
Puerto Rico was one of Spain’s two remaining colonial possessions in the western hemisphere. The island’s location on the Atlantic side of the Caribbean made it a natural stopping point for naval expeditions going to Spain other remaining colony in the Americas, Cuba. When word reached the United States in April that the Spanish were sending a squadron under RAdm. PascualCervera y Topete to break the United States’ blockade of Cuba, the American North Atlantic Fleet steamed to San Juan, Puerto Rico, in hopes of catching the Spanish flotilla coaling there. As it turned out, the Spanish squadron never stopped at San Juan. Nevertheless, RAdm. William T. Sampson ordered the port bombarded when he arrived there on 12 May 1898. The Americans withdrew after doing negligible damage to the fortifications and the city itself.
After this attack, the Spanish Army and Navy in Puerto Rico took steps to prevent future American assaults on the island’s capital. Mines were laid to defend the entrance to San Juan and the Spanish Army reinforced the shore batteries protecting the harbor. The Spanish re-located naval assets to San Juan. These included the old unprotected cruisers Isabell II and General Concha and the small gunboat Ponce de Leon. These warships were later reinforced by the torpedo boat destroyer Terror, once part of Cervera’s squadron. How much Terror added to the defense of the island is questionable. The ship had suffered a series of mechanical failures while en route from Spain and Cervera ordered its heaviest guns transferred to his flag-ship, the InfantaMaria Teresa. Cervera, concerned that the Terror’s slowness threatened the safety of the squadron, left the destroyer at Martinique with instructions to find a safe harbor as soon as possible. The abandoned Terror limped into San Juan in late May.
Because of its strategic location, both the United States Navy and the U.S. Army made plans to capture Puerto Rico. However, shortages of men, naval vessels, and transports made simultaneous attacks on both Cuba and Puerto Rico impossible. After Cervera’s squadron was discovered and successfully blockaded at Santiago de Cuba, Cuba, on 1 June, American operations were directed toward destroying the Spanish squadron there. The Army dispatched its primary force to assist the Navy in neutralizing Cervera’s ships.
While Puerto Rico enjoyed a reprieve, it was not forgotten. Acting Secretary of the Navy, Charles H. Allen, sent notice to RAdm. Sampson on 10 June directing that Navy vessels should be sent to blockade Puerto Rico and to prevent the dispatch of Spanish naval forces from there to Cuba. This move was considered necessary because inaccurate reports indicated that as many as five Spanish cruisers were at San Juan in addition to Terror. The Naval War Board and Secretary of the Navy John D. Long ordered that the port be closely blockaded and that no ships there be allowed to escape. Sampson, having to keep the Spanish squadron bottled up at Santiago de Cuba, convoy Army transports, and maintain a blockade of northern Cuba, had few ships to spare for this Puerto Rican blockade. He sent one of his weaker capital ships, the auxiliary cruiser St. Paul; and later reinforced it with a second auxiliary cruiser, the Yosemite.
St. Paul arrived off San Juan on 22 June, and was attacked by the Isabel II that afternoon. The engagement was less than spirited as the weaker Isabel II refused to steam beyond the protection of the batteries in the coastal fortifications protecting San Juan. Terror tried to join the battle, but armed only with torpedoes and two 57mm guns, the destroyer needed to get close to St. Paul before it could do any meaningful damage. St. Paul was 4,000 meters from Terror when the torpedo destroyer began “a charge” at a speed of 21 knots. At 1,200 meters Terror was poised to launch a torpedo when fire from the American auxiliary cruiser struck the Spanish destroyer, disabling its steering. A second shell punctured Terror’s engine room, flooding it and forcing the destroyer to retreat. Thus ended Spanish efforts to contest the blockade.
Yosemite arrived to reinforce St. Paul on 25 June, but ended up replacing it instead. After two of St. Paul’s batteries bent or cracked while firing during the engagement with Terror and Isabel II, the ship retired to New York City to make repairs and to re-coal. Yosemite was left unassisted to maintain the blockade of San Juan and spent its first few days off Puerto Rico fruitlessly trying to chase down blockade runners. On 28 June, Yosemite was in pursuit of a steamer believed to be the merchant steamer Montserrat, but was, in reality, the Antonio Lopez. The steamer was carrying a valuable cargo of arms. In trying to escape Yosemite, the Antonio Lopez ran aground. To protect the now-defenseless steamer, the Spanish sent out the cruisers General Concha and Isabel II and the gunboat Ponce de Leon to engage Yosemite. The Spanish were able to force the American vessel to pull back, allowing time for the unloading of the steamer’s cargo of arms, but they were unable to save the Antonio Lopez.
Unscathed in this action, Yosemite continued to maintain a tight blockade of San Juan until relieved on 15 July, by the protected cruiser New Orleans. By this time Cervera’s fleet had been destroyed and an U.S. Army expeditionary force, accompanied by a significant naval flotilla, was en route to invade the island.