I can understand differences of opinion - I can even have them with myself.
But some things are determinate - there's a correct and knowable answer. Something like, say, the status of the Social Security system.
For Congressmen not to be aware of, or to actively misrepresent the situation, is a breach of duty that cannot be explained by mere ignorance or misunderstanding.
They can disagree about what is to be done about Social Security, but not about the fact that there is no "trust fund" - benefits are paid out of federal cash flow. They can disagree about when the net cash flow reverses direction, but not that it will.
David Frum explains the true situation very well here.
The bottom line is that by obstructing repair of Social Security (as FDR himself noted would be necessary), the Dems are engaged in active malfeasance worthy of recall elections or worse.