Last Thursday, the French Senate passed a digital services tax, which would impose an entirely new tax on large multinationals that provide digital services to consumers or users in France.

Digital services include everything from providing a platform for selling goods and services online to targeting advertising based on user data, and the tax applies to gross revenue from such services.

Many French politicians and media outlets have referred to this as a "GAFA tax", meaning that it is designed to apply primarily to companies such as Google, Apple, Facebook, and Amazon — in other words, multinational tech companies based in the United States.

The digital services tax now awaits the signature of President Emmanuel Macron, who has expressed support for the measure, and it could go into effect within the next few weeks.

But it has already sparked significant controversy, with the United States trade representative opening an investigation into whether the tax discriminates against American companies, which in turn could lead to trade sanctions against France.

The French tax is not just a unilateral move by one country in need of revenue.

Instead, the digital services tax is part of a much larger trend, with countries over the past few years proposing or putting in place an alphabet soup of new international tax provisions.

These have included Britain's DPT (diverted profits tax) , Australia's MAAL (multinational anti-avoidance law) , and India's SEP (significant economic presence) test, to name but a few.

At the same time, the European Union, Spain, Britain, and several other countries have all seriously contemplated digital services taxes.

These unilateral developments differ in their specifics, but they are all designed to tax multinationals on income and revenue that countries believe they should have a right to tax, even if international tax rules do not grant them that right.