The 9/11 attacks were coordinated; why not the simultaneous mining of several vital harbors?
Only a few mines would be needed in U.S. ports to bring shipping to an immediate standstill. It is difficult to venture even a guess at how many billions of dollars would be lost.
Nearly every time underway U.S. naval vessels have been seriously damaged during the past 30 years, the attacks have come from sea mines. The simple weapons that have operationally disabled our high-tech platforms remain widely available on global arms markets. Between 1988 and 1991, the Samuel B. Roberts (FFG-58), Princeton (CG-59), and Tripoli (LPH-IO) were hit in the Arabian Gulf. Repair bills exceeded $121 million; the handful of mines that caused the damage may have cost all of $13,000.