Israel has been sending their Dolphin class submarines through the Suez Canal. Traveling on the surface, the Dolphins can travel 8000 miles without needing to refuel. Given a sub-tender in the Indian ocean, Israel's Dolphins may safely be assumed to be at or near the Straights of Hormuz. While the Clinton administration officially refused to sell Tomahawk cruise missiles to Israel, reports are that the US did supply 100 Harpoon missiles which were loaded onto Israel's Dolphins when they made a highly unusual voyage down to Diego Garcia in 2003. Whether later administrations did provide Tomahawks to Israel is unknown. Israel also manufactures the Gabriel series of anti-ship missiles, with the latest version able to fit into a torpedo tube canister launching system.
The concern here is that Israel wants the US to go to war with Iran. A Dolphin class submarine running on batteries could easily slip into the shallow waters near the coast of Iran, fire missiles at the US battle groups, and blame Iran for the attack, much as Israel ships and planes attacked the USS Liberty and attempted to blame Egypt for that attack.