land-based ICBMs are considered destabilizing because they tend to put a premium on striking first. A MIRVed missile is able to carry 3-12 warheads and deliver them to separate targets. Thereby, if it is used in a first strike, it possibly destroys many of the enemy's missile sites. Hypothetically, if one were to assume that each side had 100 missiles, with 5 warheads each, and further that each side had a 95 percent chance of neutralizing the opponent's missiles in their silos by firing 2 warheads at each silo, then the side that strikes first can reduce the enemy ICBM force from 100 missiles to about 5 by firing 40 missiles with 200 warheads and keeping the remaining 60 missiles in reserve. Thus the destruction capability is greatly multiplied by MIRV, when the number of enemy silos does not significantly increase. Both Soviet R-36M and the US LGM-118 Peacekeeper missiles were capable of carrying up to 10 MIRVs.
Negotiations
The historic agreement started on 17 June 1992 with the signing of a 'Joint Understanding' by the presidents. The official signing of the treaty by the presidents took place on 3 January 1993. It was ratified by the U.S. Senate on 26 January 1996 with a vote of 87–4. However, Russian ratification was stalled in the Duma for many years. It was postponed a number of times to protest American military actions in Iraq and Kosovo, as well as to oppose the expansion of NATO in Eastern Europe. As the years passed, the treaty became less relevant and both sides started to lose interest in it. For the Americans, the main issue became the ABM Treaty, which forbade the deployment of a nationwide missile defense system. The United States withdrew from the ABM Treaty in June 2002, a move which Russia fiercely opposed. START II did not enter into force. On 14 April 2000 the Duma did finally ratify the treaty, in a largely symbolic move since the ratification was made contingent on preserving the Anti-Ballistic Missile Treaty and thereby preserving the long-standing principle of mutually assured destruction. To be specific, Russian ratification was made contingent on the U.S. Senate ratifying a September 1997addendum to START II which included agreed statements on demarcation of strategic versus tactical missile defences. Neither of these occurred because of U.S. Senate opposition, where a faction objected to any action supportive of the existing ABM Treaty.
SORT replacing START II
However, in 2001, President George W. Bush set a plan in motion to reduce the country's missile forces from 6,000 to between 1,700 and 2,200. Thus the START II treaty was officially bypassed by the SORT treaty, agreed to by Presidents George W. Bush and Vladimir Putin at their summit meeting in November 2001, and signed at Moscow Summit on 24 May 2002. Both sides agreed to reduce operationally deployed strategic nuclear warheads to 1,700 from 2,200 by 2012. On 13 June 2002, the U.S. withdrew from the ABM Treaty, and on the following day Russia announced that it would no longer consider itself to be bound by START II provisions. Both countries continued to pursue their objectives: Russia to this day retains 54 MIRV-capable RS-20/R-36M with 10 warheads each, 40 MIRV-capable RS-18/UR-100N with 6 warheads each and 24 MIRV-capable RS-24 Yars with 3 warheads each. The United States developed Ground-Based Midcourse Defense system to protect from small-scale ICBM attack. In October 2002United States began unilateral withdrawal of MIRV and completed it by 19 September 2005. The Minuteman III is, as of 2011, the only United States land-based operational ICBM. It can potentially carry up to only 3 RVs.
