"She's leaving when the president has one of the highest approval ratings on record. From here, it can only go down. And when it does, you know who they're going to blame. They're gonna blame Andy Card!"

Andrew Card is cautioning that the president's approval rating is at an all-time high, and that when it undoubtedly decreases, the blame will be placed on him. He is suggesting that the president's success is because of his own efforts, which when the approval ranking drops, he will be the one to take the blame. He is also indicating that the president's success is vulnerable and could easily be reversed. This quote is a reminder that success is typically short lived, which it is very important to take duty for one's actions. It is also an alerting to be gotten ready for the repercussions of failure. Andrew Card is cautioning that when the president's approval score drops, he will be the one to take the blame.