Lawrence Herman is principal at Herman and Associates and a former Canadian diplomat. He practises international trade law and is a senior fellow of the C.D. Howe Institute in Toronto.

It's increasingly clear that things are going badly for the Trans-Pacific Partnership deal.

The agreement has been negotiated and all 12 TPP countries have signed it. In terms of international trade diplomacy, it's a done deal.

Story continues below advertisement

But signature alone isn't enough to bring a treaty into force. It has to be ratified, and to do that means it has to be internally approved by all the TPP parties through their own legislative systems.

In most cases, notably among Western democracies such as Canada, the United States, Australia and New Zealand, that requires action by the legislative branch and, where necessary, passage of amending statutes so treaty obligations will be met.

The big question is trying to figure out what the Americans will do. President Barack Obama's administration is four-square behind the deal, but there are powerful counterforces – and outright opposition to TPP – in Congress.

In what is a historic pattern and reflective of the division of powers in the United States, Congress has as much constitutional authority over international treaties as the president does. And the strong signals from congressional leadership – in both the Senate and the House of Representatives – is that they simply don't like this deal.

The congressional heads of the most powerful bodies, when it comes to trade – the Senate finance committee and the ways and means committee of the House of Representatives – say they won't even consider discussing the TPP without major changes. And certainly not before November's election.

All this seems perverse. So-called fast-track authority was granted to Mr. Obama by Congress to provide assurances against other countries having to renegotiate a deal that was fully negotiated and signed by the U.S. executive. Otherwise, that would give the Americans a second kick at the can, as it were – i.e., even though you've made bottom-line concessions to get a deal with us, we want even more from you if you want our Congress to approve it. Fast-track authority was supposed to put an end to that.

Given the intensity of politics around the TPP, it seems increasingly unlikely that Congress will take up consideration of the deal in the "lame duck" period – the two months after the election but before the new president and Congress take office next January.

Story continues below advertisement

If TPP is pushed off to the next Congress and the new administration, it will almost certainly spell its demise. Both nominees, Donald Trump and Hillary Clinton, have stated their unequivocal opposition to the deal. The new Congress, whether it's controlled by Democrats or Republicans, is not likely to embrace the agreement, given the current negative public mood toward trade deals of any kind.

What should Canada do?

Apparently, Mr. Obama's administration has been urging Canada and other TPP partners to ratify and send a signal of endorsement that might just help swing Congress around.

Even if that were true (which I doubt), I hardly think Canada should proceed to ratify the TPP under these circumstances. Without the Americans fully on side and congressional approval of the agreement in the bag, it would be a risky scenario for Canada to commit. While we would still have NAFTA, we would lose the benefits of increased preferences over a wide range of sectors in our largest market.

There is the possibility of Japan and Australia ratifying without the Americans. But for Canada, a trade deal without the United States would be a vastly diminished proposition.

At the very least, we should bide our time, continue with the parliamentary process, await the House of Commons trade committee's assessment and decide what to do once the situation in Washington becomes clear. That won't happen until next spring.

Story continues below advertisement

So, while it's fine to be optimistic, the reality is that's where we're at with the TPP. Sadly, the value of the agreement to the United States (quite apart from the value to a major segment of the global economy) is lost in the political cauldron in Washington.