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The other existential threat candidates must confront

It now seems within the realm of possibility that over the next few years, the most important nuclear arms control treaties -- negotiated among the world's nuclear powers over nearly four decades of painstaking diplomacy -- will have expired or been eliminated. This would open the floodgates to a 21st century arms race that could be far more chaotic and dangerous than what threatened the world following World War II.

Guatemalan boy's death is a national travesty that should be investigated

With the second reported fatality of a young child in the custody of US Customs and Border Protection this month, many are raising serious questions about CBP practices, but so far officials have provided answers that are spectacularly unsatisfying. 

We're dangerously unprepared for the heat crisis from climate change

Hot enough for you?

Well, if you live in one of the many US cities where official heat emergencies have been declared, or if you live in California, suffering the worst wildfires in the state's history, the answer is obvious. Extreme heat creates terrible conditions. And for many vulnerable individuals those conditions can be -- and often are -- deadly.

Ebola highlights public health crisis

The death of Liberian national Thomas Eric Duncan, who succumbed to Ebola in a Dallas hospital, is of course tragic. But the extraordinarily poor way his case appears to have been handled may also inadvertently have done the United States an enormous service -- not just in shining a light on the threat posed by this virus but also by revealing the profound problems both in our health care delivery system and the public health programs supposed to help prevent outbreaks, track contacts and control the spread of disease.