Tensions between Washington and Paris had been brewing for months over Emmanuel Macron's plans to introduce a tax on digital transactions in France, which takes aim at the biggest US technology companies.

But they boiled over this week when the Trump administration took the aggressive, unilateral step of launching a probe into the French digital tax to determine if it unfairly discriminated against US companies.

The investigation could ultimately lead to US punitive tariffs on French goods, sharply ratcheting up transatlantic trade tensions at a time when they are already high.

How serious is the move by the Trump administration?


What's in the French law that triggered the row?

Will the UK be the next target?


Are international efforts likely to succeed?

What's the view in Silicon Valley?