The clock is ticking down ominously on America's potential for climate change leadership, and it's worth taking stock of the historic -- and volatile -- moment we're now in.

Lost in the political storms of last week was an important cry from a key operator: President Obama's climate...

Will global warming turn into global warring?

It's a hot question in need of cool-headed analysis.

The nexus of national security and climate change is a burgeoning field, and one that's coming under some scrutiny at a time when increasingly bigger claims are being made on its behalf.

To...

"What right does someone driving a huge gas-guzzling SUV have to say to a poor Bangladeshi or Indian cooking over a wood stove to cut down their emissions?"

It's a stark framing of the global debate over climate change -- and one that Americans, as the collective driver of that...

It was the final days before Election Day 2000, and with world-historical stakes in the balance, a huge new issue had splashed into the campaign: the drunk driving of one George W. Bush, circa 1976.

Fast forward to 2004, same final pre-election period. Topic du jour? Osama Bin...

With the last debate presidential coming up, Barack Obama will have a final chance to take a forceful swing at what is perhaps John McCain's potentially most radical idea: the creation of a "league of democracies" that critics say could effectively subvert the United Nations.

McCain says he intends to...

Despite Barack Obama's recent surge in the polls, the media maintain -- as they have throughout the summer -- that the race is close, and will be so on Nov. 4. And that may be true.

But imagine if Obama's upward climb in opinion polls right now were not...

Joe Biden visits today. Yesterday, Barack Obama's campaign announced that he will visit later this week. And John McCain is scheduled to arrive this weekend.

The evidence is unmistakable: there are big stakes in tiny New Hampshire, and the campaigns are now recognizing it.

As a last-stand proving ground...