Limpet mines placed on allied ships. The primary SEALS basic training isn't much different from the old WW2, Korea, Vietnam UDT training and there is a need for Troops who are able to withstand hypothermia and paddle a rubber boat while unconscious. The problem was that the Navy kept producing SEALS when there was no realistic mission. According to Luttrell's book, the SEAL's were tapped by the CIA to be some kind of special missions group in the mountains of Afghanistan but apparently they just got in the way of long time military groups like the Army Rangers and Recon Marines. Luttrell was finally rescued by Army Rangers when his special op's group was surrounded and wiped out. The real threat of allied shipping by terrorist groups is the ideal mission for SEALS but are they up to it when there won't be much publicity?