Francois Hollande is a man on a mission—to increase the top rate of tax on income to 75 percent. The Socialist candidate, who is poised to beat Nicolas Sarkozy in the French presidential election, said, “Above 1m euros [£847,000; $1.3m], the tax rate should be 75% because it’s not possible to have that level of income.”

Hollande’s “unassailable” logic aside, the measure would remind those who are too young to remember the 1970s of what happens when the rapacious state makes work really unprofitable. I can just see the Whitehall mandarins wring their hands with joy as thousands of French high-earners, from actors to businessmen, pour across the English Channel to London. If anything, the disastrous effect of the French tax will be greater than four decades ago—the world, after all, has become even more competitive and the cost of relocation has fallen appreciably. Karl Marx is supposed to have said that “history repeats itself, first as tragedy, second as farce.” Hollande may well prove him right.