The more than 200-year-old US constitutional system has been strained, almost to the breaking point, repeatedly in the 21st century. The latest instance is potential new limitations on co-operation between the government and corporations to limit online disinformation. A Louisiana judge has ordered President Joe Biden’s administration, including public health and security agencies, not to engage social media companies with "the purpose of urging, encouraging, pressuring or inducing in any manner the removal, deletion, suppression or reduction of content containing protected free speech". That effectively bars the government from working with these platforms to try to create voluntary standards that protect the public from especially egregious and harmful disinformation. It privileges the free-speech rights of wild-eyed individuals, who could always still say whatever they want in their own media, at the expense of the same rights of private companies and the government itself, not to mention the interests of the general public and constitutional order. The century began its ongoing pattern of stress-testing the creaking US Constitution with the fraught aftermath of the 2000 presidential election between George W Bush and Al Gore. The result was a virtual stalemate, with a result in Florida that was so close it became clear that no amount of contested recounts would produce a clear outcome either way. The election was ultimately decided by the Supreme Court, which voted strictly along partisan lines to halt any further recounts in the state, handing Mr Bush the presidency. Although Mr Gore graciously accepted their ruling, not only did the electoral system appear badly broken (Mr Bush lost the popular vote), but the Court initiated a process of shattering self-inflicted delegitimisation which continues today. In addition to all justices voting in a manifestly partisan manner, they adopted stances on state authority that flatly contradicted well-established liberal and conservative positions on the issue, obviously in order to promote a politically advantageous outcome for their ideological allies. The ensuing 15 years saw disasters ranging from plainly unconstitutional torture with impunity by the government following the 9/11 terrorist attacks to the 2010 "Citizens United" ruling that unleashed a tidal wave of unaccounted-for "dark money" from wealthy powerbrokers and corporations that flooded the US political system on all sides with uncontrolled, unprecedented and legally sanctioned corruption. The arrival of Donald Trump and his "Make America Great Again" movement (which brought the Louisiana lawsuit) initiated a series of sustained challenges to the system from within that have neither brought down the US constitutional order nor been successfully suppressed. Indeed, Mr Trump remains the leading Republican candidate for the 2024 presidential nomination, and makes no secret of his intention to use his power to inflict "retribution" for his supporters against all of their perceived adversaries. One of the earliest and most alarming challenges to the constitutional order posed by the Trump movement was the mobilisation of disinformation and conspiracy theories largely through social media. It developed into an unprecedented and sustained attack on the very notion of objective reality beyond mere assertion and opinion. Most disturbingly, this attack on the very concept of verifiable truth combined internal and external forces, both working, for their own reasons, to try to secure Mr Trump's victory over Hillary Clinton. Internally to the country, Mr Trump's campaign and movement elevated fabrication, conspiracy theorising, wild speculation and baseless allegations to a campaign specialty, if not an art form. Bizarre conspiracy theories like QAnon began infecting mainstream discourse. And when the coronavirus pandemic hit, the extent of the devastation wrought by the twin campaigns against US national institutions and the category of the truth became gruesomely obvious. Vast portions of US society became militantly hostile to the evolving advice of government medical professionals, eventually declining to accept vaccinations despite their development under Mr Trump's administration. There is no telling how many of the more than 1.1 million Americans who have died from Covid-19 refused a vaccination that could have saved them. But the number may be in the hundreds of thousands. Even Mr Trump was booed by his own supporters when he once made the mistake of promoting vaccination at a rally. Mr Trump may be out of office and off of Twitter, but the disinformation threat is by no means over. His allies in Congress have been using subpoena powers to investigate, intimidate and deter disinformation researchers at universities and think tanks in co-ordinated parallel to lawsuits seeking to restrict government communication with social media companies. Those who embrace the spread of online falsehoods are naturally hostile to efforts to study and counter this malignancy. It's no surprise that Representative Jim Jordan of Ohio, one of the leading promoters of the baseless conspiracy theory that the 2020 election was stolen from Mr Trump, is leading the attack on these researchers. Meanwhile, undeterred new research shows that foreign powers sought to influence US public opinion reaction to criminal charges filed against Mr Trump. If this is true, then there is no reason to doubt that such forces, both inside and outside of the country, are preparing another onslaught against the 2024 elections, whether he is a candidate or not. When courts try to prevent government public health and security agencies from helping social media companies voluntarily create safeguards in the public and national interest on manifestly spurious "free speech" grounds, it is another depressing reminder that the US body politic seems increasingly unable to overcome even thoroughly diagnosed malignant and metastasising cancers like online disinformation.