The White House and Congressional Republican leaders joined hands this week on a strategy to advance the biggest legislative priority of the remainder of President Obama’s term. Yesterday’s 218-208 vote in the House for trade promotion authority (TPA, or “fast track”) kicks off a series of maneuvers designed to get something across the line that will allow the president to complete negotiations on the 12-nation Trans-Pacific Partnership. But the Yiddish saying of my ancestors could apply here: Man plans and God laughs.

The strategy rests on a diminishing resource in Washington: trust. The original fast-track bill was linked to something called trade adjustment assistance (TAA), or help for workers laid off as a result of trade deals. But when the House offered a two-track vote, Democrats refused to play the Washington game and pass something they like to advance something they didn’t like. So the White House/Republican team decided to split the two measures.

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The bill that passed the House yesterday, which will allow any president for the next six years to negotiate and finalize trade deals and bring them to Congress for a guaranteed up-or-down vote without amendment, was stand-alone legislation. John Boehner and Mitch McConnell have vowed that TAA will get a separate vote later. Democrats in the House and Senate, most of whom have predicated their support on both TPA and TAA passing, must take it on faith that Republicans will be true to their word.

But Pete Sessions, the Republican chair of the House Rules Committee, openly taunted Democrats on the floor on Thursday, commenting that they were responsible for the worker-aid provision’s failure. “The Democratic Party voted against the American worker last week,” Sessions said. This is a problem for the Obama-Boehner-McConnell coalition. Without assurances that TAA will get through Congress, Democratic senators may not vote to advance fast track, and Sessions was prematurely laying the groundwork to blame Democrats in that eventuality. He probably should have used his inside voice.

Republicans will try to lure Democratic support for TAA, which many rank-and-file GOP members consider welfare for unions, by pairing it with a noncontroversial bill giving trade preferences to African nations. That bill passed the House with 397 votes last week. But House Democrats on the Congressional Black Caucus torpedoed that strategy yesterday, intimating that they would still not support TAA even if linked to the African trade bill. Democratic Leader Nancy Pelosi alleged there was “no way forward” for TAA in a press conference on Thursday.

That leads to two questions. One, will the 13 Senate Democrats who supported fast track when it was attached to TAA still back it now, when TAA’s future looks so uncertain? Many have been noncommittal on that question, and they appear to want guarantees that Republicans are unwilling or unable to give.

More important, would the president sign the fast track bill into law, even if TAA doesn’t make it? White House Press Secretary Josh Earnest said earlier in the week, “The only legislative strategy that the president can support is one that will result in both pieces of legislation arriving at his desk,” but when asked whether the president would sign one without the other, Earnest dodged. “At this point, I don’t want to go into the legislative options being discussed.”

Related: Obama Is Now Dangerously Close to Lame Duck Status​

There are additional hurdles in the Senate. Fast track almost derailed there last month when a handful of supporters demanded a vote for re-authorizing the Export-Import Bank. Mitch McConnell vowed to hold that vote, but hasn’t followed through, which has sapped trust in the process. In exchange for their vote, senators could force Ex-Im re-authorization onto the TAA/African trade legislation or even attach it to fast track. That would complicate passage, because House Republicans are strongly opposed to extending the bank’s charter.

It’s darkly ironic, as economist Dean Baker has said, that the linchpin to passing a so-called free trade deal would be re-authorizing the Ex-Im Bank, which provides direct subsidies for U.S. exports at the expense of other countries, the polar opposite of free trade. But these debates seem to play out under rich people’s rules, where internal contradictions and procedural difficulties melt away.

There is one final problem for the effort, however. The Senate’s initial fast track legislation included a measure inserted by New Jersey Democrat Robert Menendez that would deny trade agreements fast-track authority if they included partners with bad records on human slavery. That would disqualify the Trans-Pacific Partnership, since the pact includes Malaysia, which ranks as a “Tier 3” nation in the State Department’s annual trafficking report, the lowest possible tier.

The White House engaged in furious negotiations to reach a compromise on the Menendez provision — a compromise on slavery — but it never managed to get a vote in the Senate. The House didn’t change the language either, even when they separated fast track from TAA. So that measure remains a problem.

Republicans want to fix it in yet another bill on customs enforcement, but in order to get some members on board with fast track, they larded up that legislation with all sorts of right-wing riders, preventing trade agreements from dealing with climate change or immigration law, among other measures unpalatable to Democrats. Boehner and McConnell said they would go to conference on the customs bill, but there’s such a wide gap between the parties that it’s unlikely any solution would be able to pass. If you think Congress deals easily with contentious legislation loaded with unrelated policy riders, you haven’t been paying attention the last couple years.

Related: Is ‘Liberal’ a Dirty Word? More Democrats Say No

So if fast track passes but the customs bill never does, would Malaysia have to get ejected from TPP? Perhaps not. The State Department’s next report on human trafficking is due soon. If they simply reason that Malaysia has made enough progress to move up a notch in the rankings, they would avoid any restrictions in fast track, without any verification of the State Department’s judgment required. The Malaysian government has already floated this as an option, despite the high-profile discovery of dead slaves in mass graves in the country. Would the White House dubiously alter reports on slavery to protect its trade agreement?

The mad scramble to secure fast track reflects a serious conviction from Obama, Boehner and McConnell in favor of what we now call trade deals, composed less of tariff reductions than favors to multinational corporations. The trio has sought every opportunity to turn these deals into reality, no matter the consequences. The public comes down largely on the other side, and the impressive coalition trying to thwart fast track still has a fighting chance. But voters often matter less in American politics than donors.

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