If you have probable cause getting a targeted warrant is not an issue. For or against Trump has exactly ZERO baring on that. If you want records for 1.3 million people you're in the realms of claiming there's a criminal conspiracy and a measurable fraction of adults in the USA are in on it.
Or you're doing dragnet on your political enemies.
It's wrong if someone working for Obama does it, it's wrong if Reagan does it, it's wrong if Hilary does it, it's wrong if _anyone_ does it. Including Trump. He's not special, he's the same whether you like him or not.