Thus, the U.S. has sought to organize its nuclear forces so that no enemy can launch a disarming first strike, mainly by fielding three distinctly different types of weapons: manned bombers, land-based intercontinental ballistic missiles in hardened silos, and sea-based intercontinental ballistic missiles on stealthy Trident submarines.

FORBES: Nuclear Weapons: How Few Is Too Few?

Gone will be the time-tested strategic Triad of intercontinental-range bombers and land- and sea-based missiles.

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