The leading French economist Gabriel Zucman is urging European governments to inflict financial pain on American billionaires in response to US President Donald Trump’s effort to seize control of Greenland, a mineral-rich island that some of Trump’s rich campaign donors see as a potentially massive profit opportunity.

“Access to the European market—by billionaires and the companies they own—should be made conditional on paying a wealth tax: in effect, a tariff for oligarchs. If Elon Musk, for example, wants to keep selling Teslas in Europe, he should have to pay it. If he refuses, Tesla would lose access to the European market.”