European Council President Donald Tusk | John Thys/AFP via Getty Images Brexit Files Insight EU-Japan trade deal — a vision of Brexit future Would Tokyo want a deal with London that mimics its agreement with Brussels? Probably not.

What does the EU-Japan deal that was announced Wednesday tell us about Brexit?

Ask Donald Tusk, and he’ll tell you (again) that it reveals just how misguided the whole enterprise is.

“We have heard statements saying that it isn’t worth being in the European Union as it is easier to do global trade outside of the EU,” the European Council president said in Brussels today, taking a clear swipe at the U.K. “Today we have shown that this is not true, that the EU is more and more engaged globally.”

In the U.K. they don’t see it like that. True to the Johnsonian doctrine of “have cake, eat cake,” ministers at the Department for International Trade are sticking to their manifesto commitment to “replicate all existing EU free-trade agreements” and to support ratification of any new ones entered into while the U.K. is still in the EU — such as the Japan deal.

In other words, the U.K. hopes that it will be allowed to piggy-back on the EU after Brexit, maintaining the same trading terms with third countries.

The complications of this policy are numerous. Why, for example, would a huge economy like Japan want the same terms with the U.K. (a smaller economy) as it has with the giant EU trading bloc? Japan made major compromises to reach this deal. With a big player like the EU, you have to. Dealing with a smaller partner like the U.K., surely Japan would seek to thrash out even better terms for its key industries, rather than just copying and pasting its compromises with the EU.

Of course, the best-case scenario for Japan would be if the U.K. secured a Brexit deal that meant it stayed, to all intents and purposes, a part of the EU trading bloc. But if Michel Barnier’s words in a speech this morning about “no frictionless trade” are anything to go by, that looks less likely than ever.

The EU-Japan deal looks like a salutary lesson for the U.K. about where it sits on the priority list for partners like Japan. The first port of call for a country seeking to realign itself after Trump dumped the Trans-Pacific Trade Partnership was not "Global Britain" — it was the European Union.

This insight is from POLITICO’s Brexit Files newsletter, a daily afternoon digest of the best coverage and analysis of Britain’s decision to leave the EU. Read today’s edition or subscribe here.