US Navy's New Floating Base Gets a Workout in Gulf A new, key addition to American-led naval efforts to ensure Mideast oil keeps flowing has emerged as an unusual mix of a ship combining decades' worth of wear and tear with state-of-the-art technology and a largely civilian crew. After winning a reprieve from the scrapyard, the USS Ponce was reborn through a rush retrofit earlier this year and turned into a floating base prowling the waters of the Persian Gulf. It is now getting its biggest workout since refurbishment as the centerpiece for sweeping naval exercises under way that serve as a very public warning to Iran. The Islamic Republic has threatened to shut the Gulf's entrance at the Strait of Hormuz, the route for a fifth of the world's oil supplies, and would likely use mines to do so. Anti-mine divers on practice drills deployed in small boats off the Ponce's stern gate early Saturday, and MH-53 minesweeping helicopters launched from the ship kicked up sea spray as they hauled mine-detecting equipment through the water. Later in the day, a U.S. destroyer pulled alongside, fighter jets roared past and gunners fired thunderous rounds from .50 caliber machine guns during a simulated encounter with a hostile vessel. Senior Navy officials in the Gulf are quick to downplay talk of conflict with Iran, which is locked in a dispute with the U.S. and its allies over Tehran's disputed nuclear program. The West suspects Iran aims to develop a nuclear weapon; Tehran denies the charges. A U.S. Navy boat is lowered to the sea from the deck of the USS Ponce, a floating base to support mine countermeasure operations, in the Persian Gulf on Saturday, Sept. More than 30 nations are participating in an exercise responding to simulated sea-mine attacks in international waters _ a demonstration of international resolve to ensure maritime security in the strategic but volatile region. U.S. military officials in the region insist the exercises, which include forces from more than 30 countries, are defensive and not directed at any country. They prefer to focus instead on the Ponce's role as an innovative new tool to help ensure security in the region, and on the need to train with allies to keep sea lanes open. Still, the message is clear. "Any extremist group, any country that puts mines in the water would be cautioned" by the exercises, said Marine Gen. James R. Mattis, the U.S. Central Command chief, during his first visit onboard the Ponce since it deployed June 1. We do have the means to take mines out of the water if they go in. We will open the waterways to freedom of navigation. Military leaders believe the Norfolk, Va.-based Ponce is central to that mission. More than half the length of most U.S. aircraft carriers, the Ponce can accommodate multiple helicopters on deck and small boats in a well deck below. The ship was originally an amphibious transport dock built at the height of the Vietnam War. Those types of vessels are typically used to carry landing forces of Marines. It's now known as the Navy's first "afloat forward staging base-interim," a name given because the Ponce is meant to be a stopgap until a similar base built from scratch is delivered. That won't happen until at least 2015. "This will more or less act as a test for using floating platforms in the sea for military operations," Riad Kahwaji, chief executive of the Dubai-based Institute for Near East and Gulf Military Analysis, said of the reconfigured Ponce. There'll be a lot of defense industry officials observing the performance of this. Much of the original ship remains, including the tight Marine-style bunks stacked four high from floor to ceiling in some parts of the ship. But there are plenty of 21st Century additions too.