When does politics trump principle?

Today from Chuck Muth:
Not long ago, when the House was considering adding the new prescription drug benefit to Medicare – the largest new entitlement since LBJ’s Great Society days – conservatives by and large were in opposition. However, former Speaker Newt Gingrich made a rather compelling case that passing the benefit would result in electoral gains for Republicans at the polls. Gingrich’s political argument ultimately won over the conservative philosophical argument.
Now the issue is Social Security reform. The president, who no longer faces re-election, is pushing for a dramatic overhaul of the nation’s Ponzi-scheme retirement program…but skittish congresscritters facing re-election again in 2006 are going “wobbly” on him. Unfortunately, as Holman Jenkins reported this week in Political Diary, Gingrich and Jack Kemp – Bob Dole’s running mate in 1996 who lost his debate with Al Gore – are siding with the Nervous Nellies, championing a “reform” package which doesn’t really reform the system.
What’s the sense of having a governing majority if you’re scared to death to govern according to the issues you supposedly believe in and got you elected?”