This morning negotiators from the United States and 11 Pacific rim countries announced that they had finally reached an accord on a free trade deal nearly a decade in the making.

From the Wall Street Journal:

For the U.S., the Trans-Pacific Partnership trade agreement opens agricultural markets in Japan and Canada, tightens intellectual property rules to benefit drug and technology companies, and establishes a tightknit economic bloc to challenge China’s influence in the region.

President Barack Obama lauded the trade accord on Monday, saying it would open new markets to American products and set high standards for protecting workers and the environment.

After dozens of rounds of negotiations and five days of haggling in Atlanta, trade ministers and other top officials said they resolved bitter fights over intellectual property protection for biologic drugs, automotive-assembly rules and dairy products.

During today’s White House press briefing, Josh Earnest tossed out optimistic talking points, saying there’s “no reason” why Congress can’t ratify the agreement in 2016.

The deal, if approved by Congress, will mark an effective expansion of the North American Free Trade Agreement launched two decades ago to include Japan, Australia, Chile, Peru and several southeast Asian nations.

The trade deal has been in the works since 2008 but has been stymied by politically sensitive disputes, including a fight between the U.S. and Japan over the automobile industry.

This amounts to a huge—and possibly legacy-building—win for Obama, but the wrangling of 11 world leaders may seem tame compared to what’s in store for him in Congress.

The Trans-Pacific Partnership, or TPP, was ripped to shreds by Congressional Republicans who railed against the classified status of the unfinished deal. Officials held TPP so close to the chest that members of Congress wishing to review the deal were unable to even read the words on the page without going through a full security detail, alone, devoid of any technology or even a pen and paper with which to take notes.

The full text of the agreement (think thousands of pages) won’t be available right away, but Republicans are already gearing up for an intense review process.

“… serious concerns have been raised on a number of key issues,” said Senate Majority Leader Mitch McConnell in a statement today. “This deal demands intense scrutiny by Congress and the legislation we passed earlier this year provides us the opportunity to give this agreement that scrutiny. In the months ahead, the Senate will review this agreement to determine if it meets the high standards Congress and the American people have demanded.”

McConnell is referring to the Trade Promotion Authority legislation that caused an uproar in Congress earlier this year. Both hardline conservatives and pro-union advocates opposed the “fast track” procedural bill (for very obviously different reasons,) making for a confusing and convoluted discussion about exactly what was happening between Congress and the Executive Branch.

That being said, don’t expect a literal “fast track” on this. We’re looking at months’ worth of TPA-mandated review in Congress covering concerns regarding intellectual property, manufacturing, tariffs, and currency regulations—which may or may not unravel everything Obama has worked so hard to set in stone.

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