Long term, altruism may always be the most practical course. In this case, since the issue is now closely connected to Gore, it certainly is.
Here's some paragraphs from an article on global warming, entirely available here LINK
…Global warming—and the other environmental disasters that will exacerbate and be exacerbated by global warming—doesn’t permit this hope. It takes forty years or more for the climate to react to the carbon dioxide and methane we emit. This means that the disasters that have already happened during the warmest decade in civilized history (severe droughts in the Sahel region of Africa, Western Australia, and Iberia; deadly flooding in Mumbai; hurricane seasons of unprecedented length, strength, and damage; extinction of many species; runaway glacial melt; deadly heat waves; hundreds of thousands of deaths all told) are not due to our current rates of consumption, but rather the delayed consequences of fuels burned and forests clear-cut decades ago, long before the invention of the Hummer. If we ceased all emissions immediately, global temperatures would continue to rise until around 2050.(Via 3 Quarks Daily. I can't keep up with them.)
This long lag is the feature that makes global warming so dangerous. Yes, this is how we would destroy ourselves—not by punching red buttons in an apocalyptic fit, but by appropriating to ourselves just a little too much comfort, a little too much warmth, a little too much time. Like Oedipus, we’ve been warned. Like Oedipus, we flout the warning, and we’ll act surprised, even outraged, when we find out what we’ve done….
…Only one feature of our otherwise forgotten 20th-century world seems likely to remain and be reinforced—the supreme importance of wealth. Rich countries will do better than poor countries, rich households will do better than poor households, rich species (Homo sapiens and their pets) will do better than poor species (all the rest). Global warming will deepen the divide between haves and have-nots—Hurricane Katrina offers a one-off example of how this can occur even in the US, but the sharper distinction will be international. As poor countries are hammered by sudden disasters and longer-term droughts, shortages, and epidemics, wealthier countries will paradoxically and perversely provide less aid, as they struggle with their own resource problems and future uncertainties. … LINK
My guess is that there is a wide spread, if unstated, awareness and acceptance of the pending horror promised by global warming. This specter is what holds together those on the top rung of our society. The rich and powerful in the corporatocracy, especially those in the marginally elite mainstream media, believe there is not enough room in the lifeboat for everyone and their inclination is to protect their seats, their privileges, at the expense of their integrity. In short, those in power have basically written most of us off and have come together to save themselves and keep the rest of us deluded and at bay; come together not necessarily in a conscious conspiracy, but in some undercurrent of recognition and agreement of who’s in and who’s out.
The altruistic course, and likely the best one, is to work to save everyone. I hope this is the foundation of what left of center Democrats stand for.