Well, the issue is that the US tends to practice Keynesian economics during downturns...and then instead of paying it forward in the boom times...they just cut taxes. This tax cut is irresponsible. If another deep international recession happens, the US will have little slack to give in order to boost the economy back up should that occur. If we raised taxes and paid off the nat'l debt some as the economy begins to heat up, it would be more responsible. Right now we are in a global economic expansion (it's not just the U.S....and giving credit for what is happening to only Obama or Trump isn't really being honest...but people can't help but credit the politician of their choice) and everything seems great, but a correction will happen eventually. And we need to pay it forward a bit to prepare.
WTF happened to conservatives, anyway? Like 6 years ago, it was nothing but "deficits, deficits, national debt." Now, crickets. A commitment to actual fiscal responsibility is something I admire about the conservative platform, but its nowhere to be found.
Oh well. There aren't too many of us "I'd like a rational, evidence-based mixed economy" proponents out there, sadly...