Union of Concerned Scientists
Dear UCS supporter,
This month marks the 55th anniversary of the Cuban Missile Crisis—a tense military and political standoff between the United States and the then Soviet Union in October 1962. That 13-day period is often considered the closest our country ever came to nuclear war. Unfortunately, current events make it feel like, once again, we are edging closer to catastrophe—this time with North Korea. In fact, beyond the dangerous words and saber rattling between President Trump and North Korean leader, Kim Jong Un, the Trump administration is pushing for more “usable” nuclear weapons as part of a hugely expensive plan to re-build the entire US nuclear arsenal. Just this week it was reported that President Trump told military commanders he wanted a tenfold increase in the size of the nuclear arsenal. In addition, the administration is threatening to tear up successful arms control agreements that have made us safer while taking other steps that will take our nuclear policy back decades. We need to work together to step back from the nuclear brink, reduce the risks these weapons pose, and build a more secure future—without the fear of global nuclear catastrophe.  —Katy
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Preventing Nuclear War: Congress Must Play a Role 
The North Korea crisis is just one aspect of an even bigger problem: the Trump administration and nuclear hawks inside and outside of Congress are reportedly pulling together plans to build more “usable” nuclear weapons and spend more than $1 trillion to re-build the entire nuclear arsenal. Meanwhile, the administration is threatening to walk away from critical US-Russian nuclear arms control agreements that make the world a safer place. Write to your members of Congress and demand that they take real leadership on nuclear weapons issues.
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President Trump is finally filling key positions within federal agencies. But will his nominees and appointees uphold the mission of the very offices they’re supposed to serve?
Laura Grego
Laura Grego
Senior Scientist
UCS Global Security Program

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Would the United States be able to defend against a North Korean nuclear-armed missile attack?  
Realistically, no. The only system designed to defend the United States from an intercontinental ballistic missile is the Ground-based Midcourse Defense system, which the Pentagon declared to be operational 15 years ago. But since 1999, the system has successfully destroyed its target in only half of its tests, and none of the tests have been conducted under real-world conditions. Even the director of operational test and evaluation, the Pentagon’s highest testing official, has acknowledged that the system has not yet demonstrated operationally realistic capability. Missile defense does not solve the problem of nuclear-armed missiles. The bulk of US effort and resources should go to ensuring these missiles are never used. Thoughtful, intensive diplomacy can reduce the risk of a crisis escalating to nuclear use and hopefully, over the long haul, eliminate nuclear weapons altogether. READ MORE 

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This Just In
Picturing the Entire US Arsenal
Policymakers and military officials often refer to the US nuclear arsenal as “our deterrent,” as if it were some sort of disembodied force rather than actual weapons. So, let’s take a look at what this “deterrent” actually consists of: More than 4,600 weapons, each more powerful than the bombs dropped on Hiroshima and Nagasaki in World War II. And about 400 of them are kept on hair-trigger alert, ready to launch in a matter of minutes if and when the president so orders. Learn more about what weapons are out there—and what they're capable of—with our new interactive infographic on the US nuclear arsenal and take action to help reduce the risk of nuclear war. READ MORE
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