Remember, impeachment does not require that the president be guilty of any crime. It is enough that the American people feel that he is not doing what they want done. Obama's current four year term was not granted to him by divine right. Obama is - or he should be - nothing more than a temporarily appointed manager of the executive branch. If the American people decide, for whatever reason, that Obama is not defending their interests, then impeaching him should be as straightforward as firing a manager who fails to follow instructions.
Nobody can read minds. If a politician says that he has changed his mind about an issue are they lying, or telling the truth? One can only say that the surest way to predict if a politician will betray you is if they have betrayed you in the past.