Reviving the original Trans-Pacific Partnership, a trade deal between 12 countries around the Pacific Rim, is technically impossible.

To go into force, members making up at least 85 percent of their combined GDP had to ratify it. Three days into his presidency, Donald Trump announced the United States was out. With 60 percent of members' GDP gone, that deal was doomed.

But on Nov. 11, another began to rise in its place, crowned with a tongue-twisting new name: the Comprehensive and Progressive Agreement for the Trans-Pacific Partnership (CPTPP).

Ministers from its 11 members issued a joint statement saying they had agreed on its core elements and that it demonstrated their "firm commitment to open markets."

The CPTPP is still far from finished, however. This inconvenient truth is unsurprising. Resuscitating the deal without its biggest member was always going to be hard. Without the U.S., uncomfortable concessions made in the old TPP can seem less worthwhile. But any attempt at a full renegotiation risked the entire deal unraveling. If countries used the opportunity to grab new concessions in their pet areas, others could make counterclaims and talks could descend into a protectionist mess.

The few unresolved areas reflect these challenges.

Malaysia wants more time to adjust to rules governing its state-owned enterprises. Brunei wants a more lenient approach to its coal industry. And Vietnam, which stood to gain most from extra access to the American clothing market, wants more time before it could face sanctions for violating the pact's labor laws.

Trade ministers from Mexico and Canada had a particularly tricky task, given their involvement in trade negotiations with the Americans about the North American Free Trade Agreement (NAFTA). Anything Mexico and Canada conceded in the TPP could then be unusable as a bargaining chip in separate talks with Trump.

The talks took a dramatic turn on Nov. 10 when it seemed as if agreement had been reached, only for the Canadians to backtrack. According to Wendy Cutler, an American negotiator of the TPP, such tactics are not unusual.

The Canadians want better access to the Japanese vehicle market and worry that a CPTPP agreement on cars will complicate the politics of NAFTA negotiations; they also want more freedom to force companies to develop Canadian cultural content.

For their part, Japanese negotiators were keen to create an incentive for the U.S. to join the CPTPP in the future. Some of the original rules could benefit the U.S. even outside the pact, blunting its incentive to rejoin. But ditching too many of them might cause the benefits of the original to be lost.

Aside from the areas still under discussion, the ministerial statement listed 20 carve-outs from the original pact. Rules that gave special treatment to express shipments, a sop to U.S. companies like DHL and Federal Express, will be suspended. So will protection for intellectual property, also fought for fiercely by U.S. negotiators.

Contentious rules allowing investors to take governments to court have been narrowed in scope. States can force investors to sign agreements waiving their right to sue under the CPTPP.

Despite these difficulties, so far the CPTPP looks impressively similar to its parent. It seems the new deal will preserve the market access agreed upon in the TPP. And although differences remain, they do not seem like showstoppers. The U.S. absence reduces the economic gains from the agreement but does not eliminate them.

The plan is to finalize a CPTPP deal in the first quarter of 2018. Even if the U.S. has rejected its own rules, others still see value in them.