The United States is boosting its military presence in Gulf waters to deter Iran's increasing threats to ships and oil tankers, in a step aimed at enhancing Washington’s role in protecting the strategic region. After arriving earlier this week in the Gulf of Oman, the USS Bataan and the USS Carter approached the Strait of Hormuz, boarding about 3,000 US soldiers to join the US bases in the Gulf. US-led maritime forces are warning ships against approaching Iranian waters.