Just before noon Eastern time, President Barack Obama was (ceremonially) sworn in to his second term of office.

His second inaugural address was strong in its embrace of progressive values — gay rights, addressing poverty, opposing gun violence, stopping voting restrictions. You can read the whole thing here.

Obama’s message, at its broadest, was that America is built and progresses through united action. That our government must actually be “of the people.” In that vein, the president devoted a paragraph to climate change.

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We, the people, still believe that our obligations as Americans are not just to ourselves, but to all posterity. We will respond to the threat of climate change, knowing that the failure to do so would betray our children and future generations. Some may still deny the overwhelming judgment of science, but none can avoid the devastating impact of raging fires, and crippling drought, and more powerful storms. The path towards sustainable energy sources will be long and sometimes difficult. But America cannot resist this transition; we must lead it. We cannot cede to other nations the technology that will power new jobs and new industries — we must claim its promise. That’s how we will maintain our economic vitality and our national treasure — our forests and waterways; our croplands and snowcapped peaks. That is how we will preserve our planet, commanded to our care by God. That’s what will lend meaning to the creed our fathers once declared.

It is fair to find this heartening. It is the strongest, broadest argument for responsible stewardship of the planet: that we have an obligation to the future.

It also contrasts strongly with Obama’s words during a less public event shortly after his reelection. From his Nov. 14 press conference:

There’s no doubt that for us to take on climate change in a serious way would involve making some tough political choices and understandably, you know, I think right now the American people have been so focused and will continue to be focused on our economy and jobs and growth that if the message somehow is that we’re going to ignore jobs and growth simply to address climate change, I don’t think anyone’s going to go for that. I won’t go for that.

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That’s a different theme. That theme suggests that we shouldn’t make a sacrifice in the moment to preserve the future. That we have primacy over our children.

What Obama said in November suggests a series of small adjustments and minor political fights. What he said today, with the whole world listening, was that those fights must be big, and that we as Americans must fight them.

Lines from his address to that effect will almost certainly be featured in appeals from his reconstituted campaign structure, Organizing for America. His argument today — while a reflection of the president’s long-standing philosophy — was a tacit “ask what you can do for your country” call that OFA will undoubtedly repeat over the coming months. Considering that call in light of a recent assessment of why key climate legislation failed during Obama’s first term is revealing.

Two different messages at two not-very-different moments. Which fight we see, only time will tell — and could hinge on who shows up for the fight.