After Connecticut Attorney General and U.S. Senate candidate Richard Blumenthal was caught in a lie about his alleged service in Viet Nam, the Democratic establishment and major media figures rallied around him, and tried to squelch, ignore or excuse the story.
Now, the Republican running for Obama's old senate seat in Illinois has been caught telling a similar lie, claiming to have won a military honor that doesn't exist.
Having made all kinds of excuses for Democratic candidate Blumenthal, Democrats can't launch a full throated attack on Republican Kirk. Having said Blumenthal's lie was "no big deal", the media can't focus on Kirk's lie.
This is why you should never excuse "our guy" for doing or saying what is unacceptable in "their guy".
If you do, the unacceptable becomes acceptable.