Imagine this: You buy a house. You like the house a lot. You find it welcoming and can imagine having a long life with that house. You particularly like the kitchen, and the neighbours seem nice. So you sign the deal and go to the bank to work out the mortgage.

Just as you get to the bank, your realtor calls. Turns out, that kitchen you liked so much? It's no longer part of the deal. Or maybe it will be. It's going to take a couple of years living in the place to sort out.

In the meantime, the sale price stays the same, and your mortgage will be just as high as before.

Would you sign that mortgage? Of course not.

And yet, that's what's happening now with Canada's Comprehensive Economic and Trade Agreement (CETA) with the European Union. The United Kingdom has voted to leave the European Union, and yet our federal government seems determined to see the deal in force by 2017.

With all the uncertainty surrounding this already deeply flawed deal, there is absolutely no rush to ratify CETA post-Brexit.

That's because the former Harper government signed the CETA deal in 2014 with a Europe that included the United Kingdom, our largest trading partner in Europe.

A lot has happened since then. The Harper government has been booted from power, and the U.K. has voted to leave the European Union. Both its national parties are in meltdown, and its new prime minister says she will negotiate her country's exit from the EU -- something that must happen within two years, once formal notice is given.

This is a problem for Canada.

A Europe without Britain is a much smaller and much less desirable partner to sign a trade deal with.

The United Kingdom is our most important trading partner in the EU, taking more than 40 per cent of our European exports and accounting for about a third of our European trade in services, including banking. Worldwide, the U.K. is our third-largest trading partner, after the U.S. and China, with some $16 billion in trade last year.

In short, a Europe without Britain is a much smaller and much less desirable partner to sign a trade deal with. That matters, a lot.

Not that it was ever a great deal, anyway. It would limit the right of all levels of government to direct procurement to Canadian companies (to ensure government spending creates jobs in Canada), threaten supply management, extends drug patents and contains only phantom advances in auto exports to Europe.

While CETA's odious investor-state dispute settlement mechanism (ISDS) was tweaked earlier this year in the face of public outcry in both Europe and Canada, it still gives too much power to corporations to sue governments over laws that may be in the public interest, but which hurt their profits.

As well, it turns out the United Kingdom is not so united. Ever since the Brexit vote, both Scotland and Ireland have made loud noises about leaving the U.K. Even in London, the financial capital of Europe that voted to stay in the EU, there's talk of separation.

And yet, Trade Minister Chrystia Freeland has said she still wants to see CETA implemented in 2017. The Minister is applying nowhere near the same degree of scrutiny to the CETA as she is with the equally-concerning Trans-Pacific Partnership agreement.

As with the TPP, there is no need to rush ratification of the CETA, and every reason to wait and see how things shake out in Europe as Britain negotiates its exit. Anti-EU forces in other countries, including France and the Netherlands, are feeling emboldened by the Brexit vote and pushing for referendums of their own. In such an uncertain atmosphere, committing to CETA seems premature, when we don't even know what Europe will look like in a few years.

I have made no secret of my distaste for CETA. It was always a bad deal. Without Britain, it becomes a pointless one.

We have, thanks to Brexit, a good reason to step back, take a harder look at the Harper-era deal and re-evaluate what we want from a trade pact with Europe, or anyone else for that matter, and negotiate a fair trade deal that truly helps Canadians.

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