Cross-posted from ThinkProgress Green.

On Jan. 24, President Obama will address Congress and the nation on the state of the union, with the chance to stir this country to action on the existential threat of climate change. Obama has the responsibility to seize the moment and finally explain to the American people the great mobilization of resources and will that protecting our homeland from a poisoned climate requires.

In a tweet to ThinkProgress Green, White House Director of Public Engagement Jon Carson promised that he would personally tell Obama that people believe he needs to talk about the science of climate change in his State of the Union address:

Obama climate tweet

Grist thanks its sponsors. Become one.

If Obama does make clear that the nation’s prosperity is already being damaged by the first glimmers of the coming onslaught of climate change, it will mark a dramatic departure from the past. Each year of his presidency, as more Americans suffered and died from the consequences of climate pollution, Obama’s discussion of global warming in his State of the Union addresses has withered.

In his 2009 address, he spoke of the need to “save our planet from the ravages of climate change” through “legislation that places a market-based cap on carbon pollution and drives the production of more renewable energy in America.” As the climate bill stalled in the Senate that year, Obama went silent. “Thus far, he has neglected to use his bully pulpit to hammer a climate science message home, thereby helping to fuel skepticism about climate science and lend support to the building backlash against the policies he favors,” climate blogger Andrew Freedman wrote in Sept. 2009. After Obama made a major speech calling for health-care reform, climate hawks hoped he would explain to Americans the need for the climate bill held up in the Senate.

Grist thanks its sponsors. Become one.

In the 2010 State of the Union, he said only he wanted to advance a “comprehensive climate and energy bill,” but then the White House avoided the subject.

I’m just not sure how you do a response to climate change if you can’t really say the words ‘climate change,'” wrote Ezra Klein in June 2010.

In last year’s State of the Union address, Obama avoided any mention of climate change, spurring dismay from climate hawks. Grist’s David Roberts called the omission a “moral failure, a failure of leadership, but also, I would argue, a political failure.”

A textual analysis of State of the Union addresses found that Obama mentions climate change far less than President Bill Clinton ever did, and less even than President George W. Bush. “From a political viewpoint, it is clear that Obama is not talking about climate change,” Robert Brulle wrote. “In my opinion, this approach has several major drawbacks, and effectively locks in massive and potentially catastrophic global climate change.” Bill Becker even wrote an entire sample speech on the climate challenge for the president.

There are many other climate hawks Obama could follow — in the past year, Sen. Sheldon Whitehouse (D-R.I.), Australian Prime Minister Julia Gillard, and AFL-CIO President Richard Trumka have delivered compelling speeches on the mandate for action to fight the greatest threat to human civilization of this generation.