The United States and Russia signed the New START Treaty—the Treaty ... on Measures for the Further Reduction and Limitation of Strategic Offensive Arms—on April 8, 2010, and it awaits Senate consideration. This statement, which appears in the preamble to New START, states that the parties recognize
the existence of the interrelationship between strategic offensive arms and strategic defensive arms, that this interrelationship will become more important as strategic nuclear arms are reduced, and that current strategic defensive arms do not undermine the viability and effectiveness of the strategic offensive arms of the parties. Nevertheless, some have questioned whether Russia's threat to withdraw from New START might have a "chilling effect" on U.S. missile defense plans and programs. When the United States and Soviet Union negotiated the 1991 START Treaty, the Soviet Union also sought to link limits on offensive nuclear weapons with limits on ballistic missile defenses. Nevertheless, when the United States withdrew from the ABM Treaty in 2002, Russia did not withdraw from START. It also provides a review of U.S. missile defense policy and summarizes data on missile defense spending during the 1980s, 1990s, and the past decade. Specifically, Russia appears to be concerned that, if the United States were to increase the numbers and capabilities of its missile defense interceptors while Russia was reducing its numbers of deployed offensive weapons, the time may come when the United States believed it had the ability to launch a first strike against Russia's strategic forces while protecting itself from Russia's retaliatory attack with its missile defenses. Further, reductions in the offensive forces on both sides would enhance the effectiveness of the missile defenses. These differences were evident in the U.S. and Soviet negotiating positions in the Defense and Space Talks. Instead, when the United States and Soviet Union signed START in July 1991, the Soviet Union issued a unilateral statement that indicated that it would withdraw from START if the United States withdrew from the ABM Treaty. Missile Defense Programs and Budgets

		BMD in the 1980s

On entering office, the Reagan Administration increased funding for ballistic missile defenses (BMD) against long-range strategic ballistic missiles; this funding had been growing since the Carter Administration. 104-106 , National Defense Authorization Act for Fiscal Year 1996) declared it the policy of the United States to 
develop as soon as possible affordable and operationally effective theater missile defenses; develop for deployment a multiple-site national missile defense system that is affordable and operationally effective against limited, accidental and unauthorized ballistic missile attacks on the United States, and which can be augmented over time as the threat changes to provide a layered defense against limited, accidental or unauthorized ballistic missile threats; initiate negotiations with Russia as necessary to provide for the national defense systems envisioned by the act; and consider, if those negotiations fail, the option of withdrawing from the ABM Treaty. Some would argue that reductions in funding and changes in program goals were due to other factors, notably U.S. adjustments to the end of the Cold War. To the contrary, U.S. spending on ballistic missile defense programs increased during the 1990s; the U.S. political commitment to missile defenses began to strengthen during the 1990s; and the United States withdrew from the ABM Treaty in 2002. The Clinton Administration initially shifted focus from the George H.W. The Obama Administration has displayed a commitment to continue expanding ballistic missile defenses through its Ballistic Missile Defense Review and with its proposed budget for ballistic missile defense programs.
The United States and Russia signed the New START Treaty on April 8, 2010, and it awaits Senate consideration. The preamble to the Treaty contains a "provision on the interrelationship of strategic offensive arms and strategic defensive arms." This statement does not contain any limits on current or planned U.S. missile defense programs. However, some analysts have questioned whether Russia's threat to withdraw from New START if the United States expands its missile defense capabilities might have a "chilling effect" on U.S. missile defense plans and programs.
Ballistic missile defenses have been an issue in U.S.-Soviet and U.S.-Russian arms control talks since the 1970s. During the Cold War, the nations sought to balance limits on offensive weapons and defensive weapons so that they could maintain "strategic stability," which refers to the ability of each side to launch a retaliatory strike after absorbing a first strike by the other side. Most analysts argued that missile defenses would undermine stability by protecting the attacking nation from the effects of a second strike; some argued that defenses could enhance stability by undermining the effectiveness of the first strike. The former construct was evident in the Strategic Arms Limitation talks (SALT), where the United States and Soviet Union agreed to limit both offensive forces and ballistic missile defenses. The latter formula was evident in the Reagan Administration's advocacy of the Strategic Defense Initiative (SDI).
During the Strategic Arms Reduction Talks (START) in the 1980s, the Soviet Union sought to link limits on offensive weapons to limits on ballistic missile defenses and SDI. The United States rejected this linkage, and the 1991 START Treaty did not contain any limits on missile defenses. The Soviet Union issued a unilateral statement indicating that it would withdraw from START if the United States violated the 1972 Anti-Ballistic Missile (ABM) Treaty. However, when the United States withdrew from the ABM Treaty in 2002, Russia did not withdraw from START.
Moreover, during the 1990s, when the United States faced Russia's threat to withdraw from START, the U.S. commitment to missile defense strengthened. In the early part of the decade, U.S. missile defense programs focused on the threat posed by shorter- and medium-range missiles, like those the United States encountered during Desert Storm. However, growing concerns in the latter half of the decade about long-range ballistic missiles fueled an increase in emphasis and growing funding on national missile defenses. The Clinton Administration initiated a program, known as 3+3, that explored the technical feasibility of deploying such defenses in the early part of the 2000s. When the Bush Administration took office, it withdrew the United States from the ABM Treaty and began to deploy long-range missile defense interceptors in Alaska and California.
A review of the budget data on ballistic missile defenses shows that U.S. funding for these programs grew steadily through the 1990s. Funding has leveled off in the past 10 years, but support for missile defense has been strong across the political spectrum in the United States. Congressional appropriations have nearly equaled the budget requests for these programs each year. The Obama Administration has also emphasized its support for ballistic missile defenses, in both its Ballistic Missile Defense (BMD) Review and its budget request for FY2011.
This report may be updated as needed.