U.S. and Russia Agree to Historic Nuclear Arms Treaty

The U.S. and Russia, which possess the largest nuclear arsenals in the world, have been steadily working to reduce their weapons stockpiles since the Cold War between them ended in 1989. However, incidents such as Russia's invasion of neighboring Georgia in 2008 have strained relations between the two powers and have made successful negotiations hard to come by.

Deal to be sealed in April

	Last April, President Obama outlined his plan to rid the world of nuclear weapons in a speech in Prague.

President Barack Obama and Russian President Dmitry Medvedev are expected to seal the deal at a signing ceremony in Prague on April 8. That date marks the anniversary of President Obama's 2009 speech in the Czech capital, when he outlined his plan for a nuclear arms-free world.

The agreement with Russia has been hailed as President Obama's most successful foreign policy achievement yet and leads into a nonproliferation conference in Washington, D.C., April 12 and 13 to further limit the spread of nuclear weapons.

New treaty cuts nuclear arsenals to lowest level in 50 years

	Each country has vowed to cut its number of nuclear warheads to 1,500 from the 2,200 now allowed.

The new 10-year treaty, dubbed the "New START," or Strategic Arms Reduction Treaty, extends and builds on several previous nuclear arms agreements between Russia and the U.S.

Nearly two decades ago, the governments agreed to the Strategic Arms Reduction Treaty of 1991, or START I, introduced by President Ronald Reagan in 1982. That was followed by Start II, which was never ratified by the Russian government.

In 2002, President George W. Bush negotiated further arms cuts with Russian leadership in the Moscow Treaty.

The New START slashes each country's nuclear arsenal to its lowest level in 50 years: within seven years, each country has to cut its deployed nuclear warheads to 1,550 from 2,200. Each side also would trim its missile launchers to 800 from the current limit of 1,600, according to the New York Times.

One sticking point between the U.S. and Russia has been the creation of a missile defense system designed to shoot down any missiles traveling toward Europe. While the U.S. says such a system is needed to ward off attacks from potential nuclear threats like Iran, many Russians believe the missile shield is targeted at them.

Ratification process could be lengthy

	Russia's legislature, the Duma, must ratify the treaty before it becomes law.

Before the New START pact can become law in Russia or the United States, each country's legislature must ratify it. This process could take months -- START I took 430 days -- and may not be finalized before U.S. elections in November.

In the U.S., the Senate must approve the treaty with a two-thirds vote. This means 67 senators will have to vote for it.

The leader of the Republicans in the Senate, Mitch McConnell, says he and other Republican senators will not agree to a treaty that would block plans for a European missile defense system. Many Republicans also question how the U.S. can verify that Russia has actually trimmed its weapon stockpiles.

For Russia to ratify the treaty, the State Duma, the lower house of its legislature, must approve it. The Duma consists of 450 members elected by popular vote to a four-year term. Half of the Duma's members are elected according to the population in their districts, much like the U.S. House of Representatives.

The other half of the Duma is elected by single-member constituencies, in the same way each U.S. state is allowed two senators. This system was adopted in Russia after the Soviet Union dissolved in 1991 and Communist rule ended.

Treaty charts path toward worldwide arms reduction

	Nine countries are currently known to possess nuclear weapons, and Russia and the U.S. have the most.

Although nine countries are known to possess nuclear weapons, only Russia has a stockpile large enough to pose a significant threat to the U.S. However, the possibility of a nuclear-armed Iran or terrorist group has made arms control an urgent international issue.

When President Obama visited Moscow last July to "reset" relations with Russia, he said the United States and Russia must lead by example to reduce the threat of nuclear proliferation.

"America is committed to stopping nuclear proliferation, and ultimately seeking a world without nuclear weapons," President Obama said. "That is our responsibility as the world's two leading nuclear powers. And while I know this goal won't be met soon, pursuing it provides the legal and moral foundation to prevent the proliferation and eventual use of nuclear weapons."

President Obama has also called for ratification of the Nuclear Test Ban Treaty, an agreement ending all nuclear test explosions, and he is seeking a stronger Nuclear Nonproliferation Treaty (NPT). The NPT was created in 1970 to limit the spread of nuclear weapons. It is based on three "pillars" -- nonproliferation, disarmament and the right to peacefully use nuclear technology for energy and medical applications.