The U.K. finally announced Monday that Huawei equipment will be banned from the country's 5G network — a big shift from its earlier policy. Back in January, the U.K. put limits on Huawei products, but stopped short of a ban. That decision "disappointed" the Trump administration, which claims the company is a security threat.

Some have speculated that American annoyance was part of the reason for the U.K. changing its mind — especially given that a post-Brexit Britain desperately needs a U.S. trade deal. But U.K. Trade Commissioner for North America Antony Philipson, who is responsible for negotiating the deal, recently told me that he'd played no part in discussions about banning Huawei.

Still, the U.K. admitted that the U.S. was responsible for the change — just in a slightly roundabout way. In May, the Trump administration started requiring all chipmakers using U.S. equipment or software to obtain a license before they could supply Huawei-designed chips — effectively cutting the company off from basically all its suppliers.

• According to Ian Levy, technical director of Britain's National Cyber Security Centre, the U.S. rule has made Huawei's products riskier. In a blog post, Levy explains that Huawei faces a "massive engineering challenge," which will likely result in it using new chipmaking processes or non-Huawei-designed chips in its products. That is "highly likely to introduce security and reliability problems," Levy writes, and will make it much harder for the NCSC to evaluate those products' security.
• The NCSC's decision shows just how much influence the U.S. has over global tech. Even if it can't ban other countries from using a company, it can hurt a company so badly that other countries have no choice but to ditch it.

But this isn't just about security. The NCSC told the government that Huawei 5G equipment already present in U.K. networks could continue to be used safely, but the government demanded network operators remove it. It's hard to see the security justification for that, giving this otherwise security-focused decision a bit of a trade war tinge.

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