Deglobalisation seems to be moving up a gear. The US House of Representatives last week passed a bill that would in effect ban TikTok in America unless its Chinese owner sells the video-sharing app. Barely 24 hours later, President Joe Biden signalled his opposition to the proposed $14.9bn takeover of US Steel by Nippon Steel of Japan, saying it was vital for America’s third-largest steelmaker to remain “domestically owned and operated”. Both moves have been portrayed, in broad terms, as linked to national security. One looks more like crude electoral politics.

There is at least a plausible case that a Chinese-owned TikTok poses a threat to US security. US officials have long feared Beijing could subvert the app to spy on, or spread propaganda or misinformation to, its 170mn American users. ByteDance, the app’s Chinese owner, has failed to convince Washington that its move to secure US user data on American-based Oracle servers is watertight.

Other potential solutions exist on data: the US could, given the legislative will, enact a ban on all tech companies, domestic and foreign, from transferring data to foreign countries. The propaganda concern is harder to deal with. About a third of US adults under 30 now regularly get news on TikTok, according to Pew Research. The sheer volume of TikTok content, and the personalised experiences its algorithm serves up, make it complex to track. US regulators have long restricted foreign-owned companies from holding TV broadcast licences; updating this rule, in effect, for social media has some logic.