Weekly Sift, 3013 - Republics don’t work just by rules, the dos and don’t explicitly spelled out in their constitutions. They also need norms, things that are technically within the rules — or at least within the powers that the rules establish — but “just aren’t done” and arouse public anger when anyone gets close to doing them. But for that public anger, you can often get an advantage by skirting the norms. And when it looks like you might get away with it, the other side has a powerful motivation to cut some other corner to keep you in check.
… As Congress becomes increasingly dysfunctional, as it sets up more and more of these holding-the-country-hostage situations, presidents will feel more and more justified in cutting Congress out of the picture.
We know where that goes: Eventually the Great Man on Horseback appears and relieves us of the burden of Congress entirely.