A factory chimney billows out smoke. (PRAKASH SINGH / AFP/Getty Images)

Monday came and went as one of the most important days in President Obama's tenure.

The Environmental Protection Agency at long last unveiled its proposal for reducing carbon emissions from existing power plants -- a first in U.S. history. The plan, first developed by the Natural Resources Defense Council, calls for a 30 percent reduction of emissions from 2005 levels by 2030 and gives states wide latitude for how they accomplish the task. This wiggle room means heavily-coal-reliant states won't have to hit the same benchmarks as those that already are more energy efficient. Effectively, we got cap-and-trade, but through EPA mandate instead of legislation.

There are all kinds of objections to this. Obviously, the fossil fuel industries and Republicans hate it, but their Pollyanna screeching about "job-killing regulations" only holds water if a) you're in a hermetically sealed bubble of disinformation and think we're not in the fight of our lives against a once-in-a-civilization catastrophe or b) you ignore all the employment that could (and God willing, will) be created by a large-scale societal shift toward cleaner energy.

On the other side, environmental groups and many scientists think these reductions don't go far enough. My response would be, "Well, what the hell is `far enough?' " The West Antarctic Ice Sheet is toast, the American Southwest is headed back to the Dust Bowl and in May the International Energy Agency released a report saying we're on pace for a 6-degree Celsius temperature rise (that's 11 degrees Fahrenheit), which is only survivable if you happen to own a bunker in the Yukon Territory.

When your task is this monumental, you've got to start somewhere, and this is a delicate needle for the Obama EPA to thread. Put forth rules too stringent and you risk a political backlash that could undo the entire plan. Or do you not think a President Rubio would love to spend his first day on the job castrating EPA regulations?

Mostly I'm hopeful because slowly, painfully, frustratingly, a true movement to fight back against global warming and its profiteers is growing -- and it's not just some BS-let's-all-change-our-light-bulbs greenwashing. Students are pressuring their universities to divest. The campaign against the Keystone XL pipeline has injected light and sound. Bill McKibben of  is planning the largest-ever climate protest Sept. 20 in New York. Only a muscular movement has a chance to create the political will for change.

I appreciate the metaphor billionaire activist Tom Steyer used last year: There are certain generational fights in public life, and if you end up on the wrong side of history on that issue, no one much cares what else you did. Slavery. Fascism. The civil rights movement. The Vietnam War. You get one chance to put your voice behind a cause, and the campaign to stop runaway climate change -- which will require humankind to change its energy, food and transportation systems basically overnight -- likely will require even more vehemence and courage than our forebearers put into those battles.

So, sure, we'll start with 30 percent reductions -- but all the hottest years and fiercest fights still lie ahead.

Stephen Markley is a RedEye special contributor.