colonizing the solar system

We have been given the imperative: we must leave this planet in search of new homes. Michael Griffin of NASA says a species on a single planet will not survive. The risks for space travel are high. People are likely to die, yet we will still do it. Griffin points out that the risk of dying on a climb up Mount Everest is 10%, yet people still continue to climb.
Who will colonize space? Americans? If history is anything to go by, it will be the world's poor and oppressed, searching for a better life.
Groundhog from the newsgroup sci.space.policy noted:

I have been around the world, and your average American is anything but a pioneer. The US citizen in a third world country: complains about the food; drinks only bottled water; can't stand the weather; won't learn the local languages; can't stand the locals; despises anything not blessed by the touch of mom'n'apple pie;pines away if he can't follow Oprah or the Superbowl on satellite TV. The pioneering type ?!!!

His cynicism is funny, but doesn't match with history. The English, you might say, were a pampered lot, living on the wealth of the Empire. Yet they kept on colonising. Of course, their colonies then attracted large numbers of those who were less well off. But it was wealth, power, and expansionism that set the ball rolling.
Furthermore, the image of the pampered American abroad is something of a fiction. Americans can be found not only in the cafes of Sydney and the pubs of London, but on the slopes of the Himalayas, the windswept plains of Mongolia, and the jungles of the Congo. Americans despite their well-comforted ways, managed to cope with the cramped conditions on a vessel to the moon and back. You won't see this adventurous side of Americans if you don't venture out of your own neigbourhood.
Rather than not being poor enough, the most likely impediment to America colonizing space is a lack of enthusiasm for imperialistic conquest. On the occasions the country has tried this, the results have been somewhat less than stellar.

links:
the space settlement FAQ