Purity is an important aspect of extremist political movements. It doesn't matter which one of them you study, there is always this enormous pressure towards purity, and the form it takes is not some internal purification through prayer or contemplation but an aggressive external program aimed at getting rid of those 'others' who are impure. The purists never see themselves as stained.
Cleansing is the form most commonly employed to achieve purity. Movements are cleansed from members who are too tolerant, too nuanced or too compromising. Just as you can't make an omelet(te) without breaking some eggs, you can't cleanse a movement without drowning a few adherents. That's just the way things are.
It is interesting to watch the current cleansing in the administration. Out go those who are seen as too accommodating towards the "enemy": other parties, other countries. This includes both high-status members of the administration and organizations such as the CIA. It also includes the moderate Republican politicians such as Senator Arlen Specter of Pennsylvania.
Listen to Jan LaRue, Chief Councel of Concerned Women for America, a group which tries to bring Biblical principles into all levels of public policy:
LaRue reiterates that softening the party's stance on civil unions, abortion and other social issues is not acceptable.
"Poll results show that religious conservatives secured this election," she says. "We expect that the policies we believe in -- and that the president has agreed with -- will succeed." And if that comes at the cost of alienating moderate Republicans, so be it. "There are still several RINO's [Republicans in name only] in the Senate in addition to Arlen. You've got Lincoln Chafee in Rhode Island who admits publicly he didn't even vote for the president. I think it would be far more honest if these folks would re-register as Democrats."
During Bush's second term, she adds, "We expect great things."
They also expect purity, a squeaky cleanness which doesn't contain the slightest tinge of complicated thinking or actual political compromises.