I'm loath to get into anything remotely political on this board because my views differ a lot from most, as most here are old, reactionary right wing and American.
(I'm old, so far left I'm not on the average political map at all anymore and European...)
But I will say that at the end of the day the reason Government in the US isn't working for the common man is because it's full of rich people, doing favors for other rich people and corporations - and when they leave office, they more often than not go right to work for the rich buddies they sold out the average Americans to while they were in office, ie the infamous "revolving door" policy. The government is the corporations, and the corporations are the government.
I would still argue that doesn't show that the idea of government working for the people is a bad one. It just shows that the American government has been subject to near-total "regulatory capture" - the groups that should be regulated (like corporations and the wealthy) have bought the regulators and they can now run hog wild, with predictable consequences for the average citizens and the nation as a whole.