Donald Trump reacted with his characteristic bravado and irrelevance. “This is years ago”, he tweeted to the news that his former election campaign chairman, the chairman’s deputy and a foreign policy aide face charges arising from the Trump-Russia investigation. “Why aren’t Crooked Hillary and the Dems the focus????”, he continued, before ending: “Also, there is NO COLLUSION!” Well, we shall see about all of that. But this is a long process and it needs to be understood as such. It took two years from the appointment of a special counsel in the Watergate affair before Richard Nixon fell on his sword. Four elapsed between the special counsel beginning his investigation and Bill Clinton’s impeachment. This will not be the final statement by the special counsel, Robert Mueller, appointed only in May to examine the Trump-Russia allegations.

It is sensible, as all this unfolds, to keep three things in mind. First, that in the old phrase, the wheels of justice turn slowly, but grind exceedingly fine. In other words, this is an orderly investigative process that has no time limits upon it. Second, remember that the initial terms of Mr Mueller’s appointment were set wide: “any links and/or coordination between the Russian government and individuals associated with the campaign of President Donald Trump” and “any matters that arose or may arise directly from the investigation”. In other words, there is much to examine and this may be only the start. And, third, remind yourself that, presidential bluster aside, this is an investigation into something exceptionally serious and unprecedented – American campaign officials perhaps colluding with a hostile foreign government in an election. In other words, and at the very least, this merits a serious approach, which is of course the opposite of Mr Trump’s childish yah-boos.

Initially, Mr Trump appeared to think that the announcements this week effectively left him in the clear. He has no grounds whatever for that view. The charges against Paul Manafort and Richard Gates, which are denied, and the guilty plea by the foreign policy aide, George Papadopoulos, raise the following possibilities: the president of the United States had a campaign chief, Mr Manafort, who, first, allegedly worked as an unregistered foreign agent for a corrupt Ukrainian government bankrolled and supported by Moscow; second, is accused of money laundering for the Russians and Ukrainians on an industrial scale; and, third, lied about it to the FBI. Mr Papadopoulos’s admission goes further. He, a member of the Trump campaign team, worked with people he knew to be tied to the Russian government to arrange meetings and gather “dirt” on Hillary Clinton, and lied about it too.

By any standards, these are serious issues. By coincidence, their seriousness took another sharp upward twist this week with the news that Russian-backed content reached as many as 126 million Americans on Facebook during and after the 2016 election. On Tuesday Facebook informed the Senate that 120 fake Russian-backed pages created posts that were received directly by 29 million US users, and reached more than four times that many through shares, likes and follows. We should therefore be clear. Russia has engaged and is engaging in a systematic attempt to shape the outcomes of elections across the democratic world with the goal of disrupting and weakening democracies. No important country is likely to be excluded from this campaign – which is why recent allegations about Russia’s role in the UK’s EU referendum should be taken far more seriously too. Clearly, however, the principal prize is the disruption of the US.

Mr Mueller’s investigation is thus a legal process into matters of almost immeasurable significance. He has rightly played it by the book. For now, Mr Trump can still ignore the implications in public. He has a new chairman of the Federal Reserve to appoint this week, and on Friday he heads off to Asia on a potentially important trip. In private, though, Mr Trump now knows this is for real. This week’s charges send a huge signal to all those who may be covered by the investigation. It is a statement of intent, a statement that the probe is real, not make-believe, and a stark warning to others that lying to the special prosecutor is a dangerous choice. The revelation that Mr Papadopoulos has been cooperating with the inquiry since July will concentrate the minds of potential defendants. It is a clear indication that others are in the frame. Mr Trump’s presidency staggers on, unique and chaotic, defying many rules of politics. But not the rule of law.