If you are old enough to remember the Cold War with Russia, you remember practice drills in school, crouching under desks to avoid nuclear fall-out. Those were the years at the beginning of the nuclear age, after atomic bombs over Hiroshima and Nagasaki had ended World War II with Japan. Over the next decades, the two super powers, the United States and Russia, built stockpiles of nuclear weapons in a standoff designed to avert war – or prevail if Doomsday did arrive.

President Barack Obama spoke last spring in Prague about his vision of “a world without nuclear weapons.” He warned of the urgent need to cut nuclear arsenals and avoid the threat of world destruction. He said it might not happen in our lifetimes, but must be a goal that all nations seek. In his speech, he also cited the dangerous possibility of nuclear weapons falling into the hands of terrorist groups. Some critics called him naïve. Others supported his vision and the fact that he had called upon all countries to work together toward the common goal.

On April 8, 2010, President Obama and Russian President Dmitri Medvedev signed an arms control treaty in Prague that continued the Strategic Arms Reduction Treaty (Start) that had expired in December. Obama described the significance of the day, “Today is an important milestone for nuclear security and nonproliferation, and for U.S.-Russia relations.” Medvedev called the treaty, “a truly historic event” that would “open a new page” in Russian-American relations. Both men agreed that Iran’s nuclear program had to be contained. And Medvedev appeared ready to join in stiffer sanctions against Iran, saying, “We cannot turn a blind eye to this.” He supported “sanctions that are targeted, that are tailored,” but opposed “an embargo on refined oil products.” The overall atmosphere of the meeting was one of harmony, in direct contrast to the rupture in relations that occurred after Russia’s war with its neighbor Georgia in 2008. The two presidents also downplayed disagreements about American plans to build a missile defense system in Europe that Russia opposes.

The treaty cuts our current nuclear arsenals: The United States has 5,000 warheads and Russia has 8,100. Here are the categories and the new limits:

• Deployed strategic warheads: U.S. has 2,100. Russia has 2,600. New limit is 1,550

• Total launchers (including nondeployed): U.S. has 1,188. Russia has 809. New limit is 800

• Deployed ballistic missiles & strategic bombers: U.S. – 798. Russia – 566. New – 700

There is no limit in the treaty for current tactical warheads that are operationally available. The U.S. has 500 and Russia has 2,000. Nor is there a limit on current warheads awaiting dismantlement. U.S. has 4,500 and Russia has 3,900. In the overall picture of nuclear weapons, China has an estimated 180 warheads, India and Pakistan have about 70 or 80 each and North Korea only a few. The number of warheads that Israel has is unknown.

There had been much negotiation back and forth before the treaty was signed. Russia wanted deeper cuts in American launchers since Moscow had already reduced the number of its costly missiles. Obama resisted since our nuclear arsenal is trifold: ballistic missiles, nuclear-armed submarines and strategic bombers. He eventually prevailed as he did over a possible missile defense system in Europe that would focus initially on short and medium range Iranian missiles. Obama had used a visit to Russia in July to narrow differences over treaty aims. The two presidents met or talked fourteen times to arrive at the final terms of the agreement.

On April 6, two days before the Arms Reduction Treaty was signed, President Obama had released his 50-page “Nuclear Posture Review,” which narrowed the potential use of nuclear weapons by the United States. The last review by President George W. Bush in 2002 had given nuclear arms “a critical role” in defending the country and its allies. It had also suggested that they could be used against enemies who attacked the U.S. with chemical, biological or conventional weapons. President Obama in his nuclear posture review says the “fundamental role” of nuclear weapons is to deter nuclear attack on the United States and its allies. However, it rules out the use of nuclear weapons against non-nuclear countries even if they attack the U.S. with unconventional weapons.There is an important exception for Iran and North Korea, described as “outliers” – countries that have violated or renounced the Nuclear Nonproliferation Treaty. Secretary of Defense Robert Gates commented to reporters about that aspect of the review, “There is a message for Iran and North Korea here. If you’re going to be a proliferator, then all options are on the table in terms of how we deal with you.” The overarching message of Obama’s Nuclear Posture Review was aimed at “challenges posed by suicidal terrorist and unfriendly regimes seeking nuclear weapons.”

On April 12, four days after signing the treaty with Russia, President Obama hosted a two-day meeting in Washington of the leaders of 47 countries to discuss how to prevent nuclear materials from falling into the hands of terrorists. Obama called this possibility “the single biggest threat to U.S. security, both short-term, mediumterm and long-term.” The presidents and prime ministers of Russia, India, Pakistan, France, Germany and Great Britain were joined by the presidents of South Africa and Kazakhstan, two countries that once possessed nuclear weapons and had relinquished them. President Obama held separate sessions with the prime ministers of India and Pakistan, countries that have taken the path of building up nuclear arsenals. Beyond the impressive symbolism of the gathering was the goal of seeking ways to better secure existing supplies of bomb-usable plutonium and highly enriched uranium. A welcome announcement on the first day of the meeting was that Ukraine would voluntarily relinquish their large stockpile of enriched uranium for safer storage and disposal by 2012.

In May, world leaders will gather in New York for the regular review conference of the Nuclear Nonproliferation Treaty. The emphasis will be on how to keep more countries from developing nuclear weapons as North Korea, no longer a member, has done and – according to intelligence reports – Iran is pursuing right now at Qum and other hidden sites. We will see if President Ahmadinejad attends the meeting and makes another aggressive statement about the sovereign right of Iran to develop nuclear power for peaceful purposes.

Joyce S. Anderson is the author of “Courage in High Heels,” “Flaw in the Tapestry,” “If Winter Comes” and “The Mermaids Singing.” She can be reached at JSAWrite@aol.com.