GOP attacks on immigrants comes to prime time Historian Jon Meacham told ABC’s “This Week” that the rules Joe Biden has won for this Thursday’s presidential debate means he has “childproofed” the debate for the child challenging him. That’s naive, of course. The child has signaled his plan to tag Biden with every violent crime committed by an undocumented immigrant. If Biden is defending that accusation, he’s losing. He has to reject the premise and “out” what Trump is really doing. Trump means to collectively punish 11 million undocumented migrants with mass roundup at the hands of the military, and to deport the lot using isolated isolated migrant crimes as a pretext. Perhaps pointing out Trump’s penchant for demonization and collective punishment of human beings he’s branded “vermin” is a more evocative counter. The subtext speaks for itself. Trump has suggested tossing migrants into gladiatorial combat for the entertainment value: The remarks are part of Trump’s broader pattern of using dehumanizing language when discussing immigrants, which during this election cycle has included broadly portraying migrants as violent criminals and saying that they are “poisoning the blood of our country.” Biden might ask Trump what happened to shooting them in the legs and moats filled with alligators. Brian Beutler joins Greg Sargent’s “Daily Blast” podcast this morning and notes that targeting most any other group for mass deportation would be beyond the pale as far as media reporting and public reaction goes. Pointing out that Trump advocates for that and where that impulse leads might…