Pre-modern historians often lament that our subjects are treated as irrelevant by society at large. While this is often true, and is certainly frustrating when it comes to convincing the general public to be interested in what we do, I’m not at all certain that it’s better when public figures feel empowered to misuse the materials of the pre-modern historian in order to serve their own agendas or to make themselves look they are of loftier minds than they actually are. (I also think it’s a problem when otherwise intelligent people respond in kind by simply re-subordinating those materials to their own agendas, but never mind that now.)
Senator Ted Cruz’s recent appropriation of Cicero (or, really, Charles Yonge’s translation of Cicero) has already been well-examined by classicist Jesse Weiner, writing for The Atlantic. I don’t think there’s a ton to add there, but I would consider the longer arc of history as well; Cicero’s militant defense of what he saw as the fundamentals of the Roman Republic did nothing in terms of the big picture to keep the Republic from turning into an Empire less than 40 years later. I’m not the kind of historian who talks about this or that person being on “the wrong side of history”, but I think it’s hard to get around the fact that Cicero was on the losing side, at the very least.
What perhaps might be more useful is considering the Empire’s relationship with its provinces, and how eventually, in 212, an emperor named Caracalla found it useful to extend citizenship to the provincials:
I grant Roman citizenship to all aliens throughout the Roman world, except the dediticii [meaning obscure], local citizenship remaining intact. For it is proper that the multitude should not only help carry all the burdens but should also now be in included in my victory. (Giessen Papyrus 40.1)
One can interrogate Caracalla’s motives — broadening the tax base? Making sure Christians were subject to Roman laws? — and there were consequences to this that were both positive and negative, to be sure, but destroying the Empire wasn’t one of them.
Maybe the Edict of Caracalla is applicable to today’s circumstances, maybe it isn’t; the point is that you can’t just do a Google search on English translations of Latin rhetoric and cherry-pick what sounds useful. Using Cicero as an out-of-context prooftext for your political aims, pro or con, is simply stupid. I think I’d rather stay irrelevant than see my area get abused by opportunistic demagogues.