The attacks on oil tankers continued. Both Iran and Iraq carried out frequent attacks during the first four months of the year. Iran was effectively waging a naval guerilla war with its IRGC navy speedboats, while Iraq attacked with its aircraft. In 1987, Kuwait asked to reflag its tankers to the U.S. flag. They did so in March, and the U.S. Navy began Operation Earnest Will to escort the tankers. The result of Earnest Will would be that, while oil tankers shipping Iraqi/Kuwaiti oil were protected, Iranian tankers and neutral tankers shipping to Iran would be unprotected, resulting in both losses for Iran and the undermining of its trade with foreign countries, damaging Iran's economy further. Iran deployed Silkworm missiles to attack ships, but only a few were actually fired. Both the United States and Iran jockeyed for influence in the Gulf. To discourage the United States from escorting tankers, Iran secretly mined some areas. The United States began to escort the reflagged tankers, but one was damaged by a mine while under escort. While being a public-relations victory for Iran, the United States increased its reflagging efforts. While Iran mined the Persian Gulf, their speedboat attacks were reduced, primarily attacking unflagged tankers shipping in the area.