The culture wars are all Trump has left:
Trump can't pass a health-care bill (at least so far). Getting a tax cut looks like it might be tricky. The wall he promised looks no closer to reality than it did six months ago. There are real questions these days about whether Republicans are capable of governance.
In that climate, all Trump and the Republicans will have left are identity politics and the culture wars. It's why Trump — after promising to be a president who would protect LGBTQ rights — came out against them. It's why he spent a Tuesday night speech describing the crimes of illegal immigrants in torture-porn detail.
And it's the reason conservatives are cheering the prospect of Kid Rock making a Senate run against Stabenow; policy, these days, matters to them much less than all the "real America" virtue signalling that the entertainer provides. For Trump Republicans, that posturing is all that seems to really matter.