A little addendum to MKH’s post last night noting that the House’s big separation-of-powers lawsuit will focus on ObamaCare’s employer mandate, not O’s immigration policies. Immigration was what inspired Palin to write her impeachment op-ed; it’s certainly a livelier issue at the moment than O-Care is. Why skip it?

You already know part of the answer. Like I said Wednesday, it would be weird for Boehner to have spent 18 months calling for comprehensive reform in the name of impressing Latinos, only to turn around and sue O for using his executive power to give DREAMers a break on deportation. I thought there was still a chance that immigration would end up in the suit, maybe because the border crisis had forced Boehner’s hand politically or maybe because Boehner was worried about O’s next executive amnesty and wanted to try to preempt it in court, but the politics of suing over immigration were going to be dicey no matter what. No surprise that he chose in the end to skip it, especially at a moment when even Republicans like John McCain are risking a Latino backlash by demanding more enforcement.

But there are other reasons too. For starters, Boehner may be betting that the border crisis will quiet down before fall and ObamaCare will reemerge as a key election issue, especially when the 2015 premiums are released. If he’s right, a lawsuit based on the employer mandate will be more salient than one based on immigration. If he wins and the mandate is forced to take effect, no biggie: There’s almost certainly a consensus in Congress at this point to repeal it. Beyond that, though, my sense is that he’s got a stronger case in attacking the mandate than he does attacking DACA, Obama’s 2012 amnesty for DREAMers. The latter can, kinda sorta, be defended as an act by the executive to prioritize among removal cases for a system that’s heavily backlogged. We need to take kids off the list, he’ll say, because America’s deportation machinery simply can’t cope. By contrast, there’s really no logistical excuse for not enforcing the mandate. The law is unambiguous. Obama’s clearly in violation. His argument will be that the executive needs a little leeway when a new program is being implemented, but that’s a hard argument to make given that his party wrote the law and he signed it. If he wanted some leeway, he should have added it to the bill.

So Boehner’s playing his strongest hand. And that’s very important in this case because, as Mark Levin rightly argued the other day, the stakes of losing are potentially high. If a federal judge throws this suit out, Obama will spin it as legal vindication for his executive power grabs, which of course means more power grabs. Meanwhile, Boehner will have no options left except cutting off funding for government projects, which risks a small, ephemeral backlash a la the aftermath of last year’s shutdown, or impeachment, which risks a much nastier backlash. If it turns out that the suit ends up languishing in court for the rest of O’s term and never ends up being resolved, Boehner can probably live with that. He’ll tell righties that he showed his good faith by bringing the suit in the first place, now leave him alone. He can’t live with losing, though. That’ll leave him in a spot.

Exit question one: As Byron York said on Twitter last night, it’s a little … odd that the GOP, which has voted to repeal ObamaCare 50 times or so already, is now suing Obama to enforce it, huh? Expect Democrats to have fun with that. Exit question two: What if the suit’s languishing next year and O finally follows through on that mass amnesty he’s planning? Does Boehner amend the suit to include immigration at that point? Does he cut off funding for something? Or does he dare not do any of that, given that the GOP’s presidential field will be nervous about how Latinos will react?