The problem with true idealists in politics is that few true idealists are able to compromise, and no government, particularly a democratically-based government, works without compromise. 

The problem with most professional politicians is that their ideals are subservient to their desire to retain office, and to remain in office they will vote for popular but unwise policies and legislation. While popular opinion can be fickle, most widely held popular beliefs are simplistic ideals, all too often at variance with reality.

Thus, the combination of idealists and professional politicians mitigates against compromise and practicality, and the less that government accomplishes the stronger people’s beliefs become, in turn reinforcing the problem of polarization, largely because those beliefs are rooted in images only loosely connected to physical reality.

We see that today in the debate over immigration, where one side is convinced that the situation is urgent and the most important problem facing Congress, while the other side minimizes a non-functional bureaucracy that needs overhaul and more funding.  Yet the one side ignores the fact  that the immigration problem is in fact far less severe than it was a decade ago and that, while the immigration system needs funding and fundamental reform, building more walls won’t solve anything and would be a waste of money, while the other side wants what amounts to more open immigration without coming up with a coherent program for dealing with immigration. 

To top it off, neither side in Congress wants to really deal with the problems in Latin American countries that have led to the current flow of immigrants.  And because Congress can’t come up with a unified solution with enough votes to override a Presidential veto, Trump will continue his posturing and fear-mongering  until Congress smartens up… or caves in.

I’m wagering on a cave-in.