One of the most contentious issues in the British general election was the possibility of US pharmaceutical companies driving up National Health Service (NHS) drug prices in a post-Brexit US-UK free trade agreement. In late November, Labour Party leader Jeremy Corbyn announced that a trove of leaked documents proved that drug pricing was already on the table in preliminary negotiations, and he repeatedly accused Boris Johnson of planning to “sell off” the NHS to US corporate interests. Indeed, the US government and pharmaceutical companies have made no secret of their ambitions to open the NHS up to US investment under new trade arrangements; Johnson himself has denied that the NHS will be on the table in trade negotiations.

Johnson isn’t to be believed — not only because of his known mendacity and opportunism, but because history shows that the NHS has long been vulnerable to pressure and interference from US interests. From the beginning of the NHS in the late 1940s, the health service has often been at the center of US-UK diplomacy and trade agreements, with far-reaching consequences for NHS funding and patient care.

In a mirror to today’s post-Brexit tumult, the NHS was founded in 1948 in the context of unprecedented trade and financial arrangements with the United States. Clement Attlee and the Labour Party had won the 1945 general election largely on the promise of building an expansive welfare state with a free and universal National Health Service as its centerpiece. Yet in an economy still devastated by the war, it remained an open question as to how the country could finance it.