I was just thinking about a situation like this. I was a contractor working on a Navy contract years ago. They sent me and my boss to the "kickoff meeting" in another city to discuss the expectations of the customer and fine tune what we were going to deliver. The customer, a Navy Senior Chief, asked for things that were outside the scope of the contract and my boss readily agreed to provide them.
On the ride back home I told him that there was no way that we could provide what they wanted using our software and methods. He said, "Don't worry about it. Those guys will all be on sea duty by the time we deliver and none of the new guys will know what was said at this meeting."
That seems to be the theme in politics, too. Promise them anything just to get into office.
My first assignment as a project manager was the equivalent of being promoted to captain of the Titanic after it hit the iceberg. All I could do was save some of the people on the contract.