The greatest evil here is that liberals are holding Conservatives to a standard that they themselves do not believe in.
Alinsky's Rule No. 4: Make the enemy live up to their own book of rules. You can kill them with this, for they can no more obey their own rules than the church can live up to Christianity.
This tactic is genius in its simplicity. It discredits your enemy by pointing out the ways in which they fail to be perfect. No one is perfect and so the rule is not only powerful, but permanently keeps your target on defense without the ability to push forward with ideas or a cause.