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U.S. Reveals Nuclear Force Plan, Arsenal Levels
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Tom Z. Collina

The United States will retain up to 420 intercontinental ballistic missiles (ICBMs), 60 nuclear-capable bombers, and 240 submarine-launched ballistic missiles (SLBMs) under the New Strategic Arms Reduction Treaty (New START) with Russia, the Obama administration announced May 13. This new force structure was provided to the Senate as part of the materials transmitted with New START for ratification. In addition, as part of the administration’s effort to show progress on disarmament at the May review conference of the nuclear Nonproliferation Treaty (NPT), the Department of State announced April 27 that the United States had 1,968 “operationally deployed” warheads at the end of 2009, and the Pentagon announced May 3 that as of last Sept. 30, the U.S. nuclear stockpile stood at 5,113 warheads.

Although New START limits were announced in March, the Pentagon had not made clear how it would distribute its ICBMs, SLBMs, and bombers to make up a treaty-compliant force of 1,550 deployed warheads and 700 deployed delivery systems. A White House document transmitted with New START May 13 provides further details:

•  The United States currently has 450 ICBM silos. Under the “baseline plan,” the country will retain up to 420 deployed Minuteman III ICBMs, all with a single warhead.

•  The United States currently has 94 deployable nuclear-capable bombers. Some will be converted to conventional-only bombers (not accountable under New START), and up to 60 nuclear-capable bombers will be retained.

•  The United States currently has 14 strategic nuclear submarines (SSBNs), all of which will be retained. The United States will reduce the number of SLBM launch tubes from 24 to 20 per SSBN and deploy no more than 240 SLBMs at any time.

This planned force structure under New START reduces deployed ICBMs by 30 from current levels, reduces nuclear-capable bombers by 34, and reduces SLBMs from a current force of 288 to 240. (The 14 Trident submarines contain 24 missile launch tubes each, or 336 tubes total. Two submarines are in dry dock at any given time with no missiles aboard, for a total of 288 missiles currently deployed.) The biggest surprise may be the large number of bombers being retained, given that they are not on alert or loaded with weapons in peacetime and thus are widely considered the least significant leg of the nuclear triad. One factor in this decision may have been the New START counting rule that allows each bomber to be counted as “one” deployed warhead, even though bombers can carry up to 20 nuclear weapons.

Compared to current deployments, New START would reduce deployed U.S. delivery vehicles by 18 percent and warheads by 11 percent, counting each bomber as one warhead. Compared to treaty limits set by the 1991 START I and 2002 Strategic Offensive Reductions Treaty (SORT), New START would reduce deployed U.S. delivery vehicles by 50 percent and accountable warheads by 30 percent. Adding up the planned deployments for delivery systems under New START totals 720, which is 20 above the treaty’s cumulative limit. Because the treaty allows for 800 deployed and nondeployed launchers, however, removing 20 delivery systems from deployment and placing them under maintenance would allow the United States to meet the limits. Under the treaty, the new force structure does not have to be reached until seven years after the pact’s entry into force. As strategic forces are reduced under the treaty, those that remain would be upgraded. Over the next decade, the administration plans to invest $180 billion to modernize the nuclear weapons complex and nuclear delivery systems.

Historical Stockpile Levels

In addition to revealing the total stockpile size and operationally deployed stockpile for last year, the Pentagon on May 3 released stockpile numbers for each fiscal year from 1962 to 2009. According to those figures, the U.S. stockpile reached its peak in 1967, at 31,255. It declined gradually thereafter to 19,008 in 1991, and then, with the signing of START I and the dissolution of the Soviet Union, dropped swiftly to 10,979 in 1994, the year START I entered into force. The stockpile hovered around 10,000 until 2003, when SORT entered into force, declining to 5,113 by 2009.

These numbers include strategic and tactical warheads, both active and inactive, the May 3 Pentagon document says. According to the document’s definitions, active warheads are “maintained in an operational, ready-for-use configuration” and have tritium bottles installed. (Tritium is a limited-life gas that boosts the explosive yield of the warhead.) Inactive warheads are nonoperational, with tritium bottles removed, the document says. The “operationally deployed” force, a subset of the active stockpile, stood at 1,968 in 2009, according to the April 27 State Department document.

These numbers do not include “several thousand” warheads that have been retired and are awaiting dismantlement, estimated to be roughly 4,500. In its May 3 document, the Pentagon said the United States had dismantled 8,748 warheads from 1994 to 2009 and the number of nonstrategic weapons had declined by approximately 90 percent since 1991, when President George H.W. Bush announced unilateral withdrawl of many tactical weapons.

The document stated, “Increasing the transparency of global stockpiles is important to nonproliferation efforts, and to pursuing follow-on reductions after the ratification and entry into force of the New START…that cover all nuclear weapons: deployed and non-deployed, strategic and non-strategic.”

Responding to questions about whether Russia would follow the U.S. example and disclose its own stockpile numbers, Russian Foreign Ministry spokesman Andrei Nesterenko told a May 12 press briefing, “Washington’s move, in our view, will increase transparency and serve to strengthen the trust between nuclear and non-nuclear states.” He said that Russia, after entry into force of New START, “will also be able to consider in practical terms the question of disclosing the total number of [its] deployed strategic delivery systems and their warheads.”

On May 26, British Foreign Secretary William Hague announced in the House of Commons that the United Kingdom’s “overall stockpile of nuclear warheads will not exceed 225 warheads.” That was the first time the size of the total British stockpile was revealed, although the United Kingdom had previously announced that it had up to 160 “operationally available” warheads. The additional warheads are for “logistic management” so as to maintain the operational force, according to a statement by the Foreign and Commonwealth Office. “We believe that the time is now right to be more open about the weapons we hold,” Hague said. France declared in 2008 that it was reducing its arsenal to fewer than 300 operational warheads.

Table 1: U.S. Strategic Nuclear Forces Under New START

This table shows how the deployed U.S. strategic nuclear stockpile will decline between 2010 and 2017, when reductions under New START would be completed, assuming the treaty takes effect this year. Current delivery vehicle numbers and the Pentagon’s plan for reductions under New START were announced May 13. Warhead numbers as of 2009 were announced by the Department of State April 27. The planned 720 deployed delivery vehicles under New START will need to be reduced to 700 by, for example, moving 20 to nondeployed status to comply with the treaty limit. Under New START, each bomber is counted as one warhead, but in fact can carry up to 20. On May 3, the Pentagon, revealing exact stockpile numbers for the first time, said that as of 2009, the United States had a stockpile of 5,113 strategic and tactical warheads. That number includes active and inactive weapons, but does not include an estimated 4,500 warheads that have been retired and are awaiting dismantlement.

Shaded warhead numbers are estimates based on the known number of deployed delivery vehicles, the known total number of deployed warheads, and typical warhead loadings.

2010 2017

Delivery Vehicles


Delivery Vehicles



Minuteman III






Trident II D5





Strategic Bombers









Total Deployed





Total Stockpile



Posted: June 4, 2010