During the last government shutdown in 2013, when Republicans demanded defunding Obamacare, they were at least willing to follow through on that demand. The government was closed for more than two weeks before the GOP relented. That served notice to Democrats that Republicans were at the very least willing to go all-in on their strategy and follow through — that they weren’t bluffing when they made such demands in order for a bill to pass. And that made their threats on other things seem more legitimate.
Trump has shown no such inclination to make it so people take his demands at face value. And given what’s happened in the first two legislative debates, the next time he draws a line in the sand, you can bet lawmakers know how easily it can be raked over.