As The Guardian has noted this morning:

A federal trade court on Wednesday blocked Donald Trump from imposing sweeping tariffs on imports under an emergency-powers law.

The ruling from a three-judge panel at the New York-based court of international trade came after several lawsuits arguing Trump has exceeded his authority, left US trade policy dependent on his whims and unleashed economic chaos.

“The Worldwide and Retaliatory Tariff Orders exceed any authority granted to the President by IEEPA to regulate importation by means of tariffs,” the court wrote, referring to the 1977 International Emergency Economic Powers Act.

“The court does not pass upon the wisdom or likely effectiveness of the president's use of tariffs as leverage. That use is impermissible not because it is unwise or ineffective, but because [federal law] does not allow it,” a three-judge panel said in the decision.

I offer little apology for quoting this at length: this ruling is of major significance.

Not only has Donald Trump now been shown to have started an international trade war that has massively disrupted the way in which the world's economies work in a way that is likely to have lasting implications, but what is also clear is that he did so illegally.

There should be no surprise about the fact that this move on his part was illegal. The legislation that he used to justify his actions did not even refer to tariffs.

Nor was there, as he claimed, an emergency that might justify what he did. Stable inflation and reasonable growth did not represent an economic crisis, whatever he might have thought of Joe Biden.

In that case, the decision of this court, which is binding, was predictable, although in the turmoil that is now commonplace in the USA, predictability has ceased to be a quality within government.

So why was it that Trump and his advisers thought that they could put such tariffs in place? I suggest three things.

Firstly, Trump thought he was above the law.

Secondly, he imagined that if a legal challenge arose, he could force judges into submission.

Thirdly, he thought that, de facto, such a challenge would arrive too late to have any impact: what he wanted would by then have been done and become established practice.

Has he succeeded? I suggest he has not.

He has been shown to abuse the law.

Time and again, courts have ruled against him despite his massive efforts to intimidate judges in a fashion that shows complete contempt for the rule of law.

Third, he can try to ignore this ruling, but if he does, corporate USA will, I suspect, move against him with lawsuits protesting that they need not pay these tariffs that have been illegally imposed. The consequence is that trade will be massively disrupted whilst these issues are resolved, at cost to the people of the USA.

Some of them will support Trump. The MAGA are quite indifferent to the rule of law. They think the fact that Trump flouts it is a symbol of all the good that he is doing.

Many more will realise that what they are up against is an administration that is wildly out of control.

Will that have an impact? I suspect it will, but what the consequence will be is what matters.

Will Trump allow free and fair elections?

And will the provision in the Big Bad And Ugly Bill that has now moved from the House to the Senate be passed by the upper house, letting him ignore such rulings with impunity?

We do not know as yet. There are still too many variables in play to be sure what will happen here. But do not doubt, this ruling is significant and represents a decided spanner in the works for Trump, for the time being at least.