|Fig. 1: Minuteman III ICBM in a Missile Silo. (Source: Wikimedia Commons)|
Since nuclear weapons were introduced at the end of World War II, the United States has been dedicated to building and maintaining a nuclear arsenal to deter large military conflicts. The United States military believes that its nuclear triad is the best method for deterring threats. This triad is composed of a fleet of airborne nuclear capable bombers, ballistic-missile carrying submarines, and lastly, land-based intercontinental ballistic missiles (ICBMs).  Throughout the Cold War, and until now, each of the triad's three legs has served a strategic purpose for maintaining national security. However, the triad's conception came amidst a different technological landscape, and drastic improvements in stealth capabilities and ballistic missile accuracy could leave the land- based ICBM arsenal unnecessary. With today's technology, stealth aircraft and submarines are largely undetectable by enemy forces and have the ability to effectively penetrate air defenses and deliver payloads to a target.  Additionally, these forces are mobile, and much less vulnerable to pre-emptive strikes than the land-based ICBM silos, which are located in fixed and known locations.  This information and technology poses an important question: if nuclear bombers and submarines are able to serve the same purpose as the fixed ICBMs, and are not vulnerable to a first strike, then should the U.S. military phase out its land-based ICBM arsenal?
This section will detail the current U.S. nuclear arsenal and its capabilities. The U.S. Air Force maintains a force of 400 missile silos, which are all ready to launch a Minuteman III ICBM (see Fig. 1).  Each of the 400 Minuteman IIIs carry one warhead, of which has a yield equivalent to 300-kilotons of TNT and has a range of over 4200 miles.  The U.S. Navy maintains a force of 14 Ohio-class ballistic missile submarines, each of which operate with 20 ballistic missile launchers, numbering 280 in total.  The submarines carry the Trident II D5LE submarine launched ballistic missile (SLBM), which can carry up to 8 warheads, giving each submarine an approximate load of 90 warheads.  These missiles are capable of delivering various payloads for specific operations. The two main warheads, the enhanced W76-1 and the W88, have yields of 100-kilotons and 455-kilotons respectively.  Lastly, the Air Force maintains a large fleet of nuclear capable, strategic bombers. This includes a fleet of 20 nuclear capable B-2 bombers and 66 nuclear capable B-52H bombers.  Each B-2 can carry upwards of 16 nuclear bombs (of which are gravity bombs), and each B-52H can carry 20 air-launched cruise missiles, giving this leg of the triad an estimated total of 980 nuclear weapons.  In total, the U.S. Defense Department, in 2018, reported an estimated stockpile of 4000 nuclear warheads, of which could be delivered by more than 800 ballistic missiles. 
The fixed ICBM leg of the U.S. nuclear triad, being vulnerable to pre-emptive strikes, carries a lot of risk that could escalate into conflict. Former commander of the U.S. Joint Chiefs of Staff, James Cartwright, has argued against this leg of the triad, seeing it as excessive for deterrence and inherently risk prone.  Given that strategic bombers and nuclear submarines can more effectively perform the same task as ICBMs, the ICBM force may be seen as excessive in today's military landscape. Additionally, the current strategy for using land-based ICBMs poses incredible risks that could accidentally start a nuclear war. Knowing that the ICBMs are located in fixed silos and are vulnerable to a first strike, the U.S. has maintained the policy of launching the missiles upon warning of an attack.  It would only take one false alarm for the President to authorize a counterstrike that could lead to total nuclear war. One final issue with the ICBM arsenal is that it is becoming old and requires expensive modernization. A statement from the Congressional Budget Office estimates the cost of modernizing the nuclear triad to be over $1 trillion over the next 30 years.  Former Secretary of Defense William Perry, along with Cartwright, believe that the U.S. should not replace the land-based ICBMs, and that doing so would save $149 billion.  In summary, the U.S. arsenal of fixed ICBMs can be seen as an excessive deterrent, inherently risky and a possible cause of accidental nuclear war, and unaffordable.
With modern military technology, the U.S. land-based ICBM arsenal is becoming less necessary as a deterrent to global conflicts. Its SLBM and strategic bomber forces serve the same function as the fixed ICBMs, while being less susceptible to pre-emptive strikes. With upcoming funding needed to modernize the U.S. nuclear triad, the Department of Defense should reevaluate the purpose its weapons serve. Phasing out or reducing the fixed ICBM arsenal could do a lot to balance the military's budget as well as ensure that the nation employs an appropriate strategy for maintaining national security. In all, nuclear weapons are a vital part to U.S. national security strategy and their role as a deterrent should be fully understood as the world progresses further into the 21st century.
© Jack Little. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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