“But they can’t attack Trump for his nationalism without calling attention to their own globalist anti-nationalism. So they attack him for his populism and lack of conservatism.”
You have a good point about Trump’s nationalism. However, I think you are confusing exactly who opposes Trump. The GOPe oppose Trump for similar reasons they oppose Cruz. It has to do with their staying in control and maintaining power. It is NOT because he is a populist, per se. Ultimately, the GOPe wants a candidate who is NOT conservative. But you are right about them opposing his border enforcement plan, which is an extremely conservative position on his part.
I am not OPPOSED to Trump in my criticism so much as I am unconvinced of his genuine commitment to govern conservatively. Too many tale-tale signs indicate he will shift left. I am willing to throw in my support, but not unconditionally.
So Trump is experiencing resistance by GOPe and the very conservative voters for two different reasons.
I was speaking only of the GOPe and their media & corporate supporters. For them the threat of Trump is not a question of conservatism or populism. They have embraced RINOs far less conservative then Trump and would be overjoyed by a populism that brought in an avalanche of "silent majority" voters supporting the GOPe's globalist core-principle of open-borders and "free-trade."
But Trump is appealing to and bringing in an avalanche of voters supporting an "America-First" nationalism. It is that nationalism that the GOPe and their media & corporate supporters see as such a threat to those globalist core-principles.
The above is not to say the GOPe doesn't at the same time oppose Cruz for being genuinely conservative and as such a threat to their power. But the difference is there is no open "Stop-Cruz" movement and there is an open "Stop Trump" movement. And that is due to the outspoken nationalism of Trump and the unwavering nationalism of his supporters