CALL it the “Al Capone trap”. Ever since the authorities used tax evasion charges to jail the notorious Chicago crime boss in 1931, the idea has taken hold that federal prosecutors work a bit like legal vigilantes: using any weapon that comes to hand to achieve their sworn mission, which is always to take down the biggest bad guys they can, by any means necessary.

That is not how Robert Mueller, the lantern-jawed special counsel and former FBI chief, sees his mission, say well-informed former federal prosecutors. Mr Mueller’s mission is not to topple President Donald Trump and claim a political scalp. Mr Mueller’s—deadly serious—mission is to investigate Russian government efforts to interfere in the 2016 presidential election, and whether there was any coordination between Russia and the Trump campaign in those efforts. There is an important difference between those two possible missions, even if they may end in a similar place, namely grave political jeopardy for the 45th president.

That distinction should be borne in mind when trying to make sense of the first indictments to be handed down as part of the Mueller probe. After months of work, the special counsel publicly charged Paul Manafort, the former Trump campaign chairman, and Richard Gates, a former campaign official, with 12 counts including money laundering, concealing overseas bank accounts from tax authorities and failing to register as foreign agents of the government of Ukraine. They have both pleaded not guilty. The charges all date back to lucrative work that Mr Manafort and Mr Gates undertook for pro-Russian politicians and oligarchs before signing on with Mr Trump. Mr Manafort, a dapper, bouffant-haired strategist-for hire, has long been a fixture in the murky world of post-Soviet politics. In collateral damage seized on by Republicans, Tony Podesta, a Democratic super-lobbyist, stepped down after being quizzed over his firm’s tardiness in declaring work on Ukraine for Mr Manafort.

Charges against Mr Manafort had been expected for a while, ever since the FBI mounted an early-morning raid to search for evidence at his home near Washington, DC. This signalled that a judge had been persuaded that probable evidence of a crime existed, and that Mr Manafort might try to destroy it. Mr Trump was quick to tweet out: “Sorry, but this is years ago, before Paul Manafort was part of the Trump campaign. But why aren’t Crooked Hillary & the Dems the focus?????” then “…Also, there is NO COLLUSION!”

The president is right that the indictments against Mr Manafort and Mr Gates do not refer to work undertaken for the Trump campaign. Alas for Mr Trump, a third member of his presidential campaign team is now also in the legal line of fire, namely the somewhat obscure figure of George Papadopoulos, a young foreign policy adviser to the campaign. Mr Papadopoulos’s woes are directly linked to something that looks a lot closer to collusion. According to a plea deal unsealed on October 30th Mr Papadopoulos has pleaded guilty to telling lies to FBI agents. Specifically, those lies were an attempt to conceal his contacts in late April 2016 with a professor peddling what he called “dirt” on Hillary Clinton, held by senior Russian government officials and based on “thousands of e-mails”. That timing is striking. The world only learned in June 2016 that thousands of embarrassing e-mails belonging to the Democratic National Committee had been hacked and stolen, allegedly by Russian agents. Mr Trump at that time called the DNC leaks a distraction and suggested that the Democratic Party headquarters hacked itself. In October 2016 the WikiLeaks anti-secrecy website leaked thousands of e-mails hacked from the account of John Podesta, the chairman of the Clinton campaign. Again Mr Trump challenged reports that the hacking was the work of Russian intelligence.

The response from the White House and from friendly conservative commentators was a ferocious barrage of assertions that the real Russian collusion scandal involves not Mr Trump, but Mrs Clinton, his erstwhile Democratic rival. Drawing on recent reports that the DNC paid for opposition research against Mr Trump, involving sources in Russia, the White House press secretary, Sarah Huckabee Sanders, declared that: “There is clear evidence that the Clinton campaign colluded with Russia to smear the president” and that “it might not be a bad idea” for Congress to investigate Mrs Clinton.

Ms Sanders further dismissed Mr Papadopoulos as a volunteer member of an advisory committee, with an “extremely limited” role in the campaign.

To make sense of this flurry of confusing charges and counter-charges, go back to the Al Capone trap. The White House and allies are, in effect, attempting to argue that Mr Mueller is going after the wrong villain. Their line of attack is tantamount to saying: Mrs Clinton is the Public Enemy Number One, not Mr Trump. Go after her and lock her up.

But that is to misunderstand, wilfully, Mr Mueller’s work. The special counsel’s true target is not Mr Trump or Mrs Clinton. Ot is Russia, the hostile power that attacked American democracy.

All of Mr Mueller’s actions, including his indictments and the plea deal with Mr Papadopoulos, need to be seen in that light. If Mr Mueller were to succeed in jailing Mr Manafort, and in publicly shaming Mr Papadopoulos, he would have achieved very little if his probe does not expose what Russia really did during the American election of 2016, and why.

A well-informed former federal prosecutor offers a neat way to escape from the Al Capone trap. Remember, he says, that prosecutions can sometimes be a means as well as an end. “We use prosecutions as both outcomes and inputs,” he says. Put another way, the feds use solid, easily provable charges to put pressure on potential witnesses to turn and co-operate. Mr Mueller is hoping that a fear of federal prison makes Mr Manafort and other campaign high-ups start to talk about what they know. The world has already learned that the same tactic worked on Mr Papadopoulos. His unsealed plea deal ends with the note that the former foreign policy adviser was arrested in July 2017 for lying to federal agents, and that following his arrest Mr Papadopolos, who has pleaded guilty, “met with the Government on numerous occasions to provide information and answer questions.”

Maybe, perhaps even probably, more indictments will follow. But, says the former prosecutor: “There are many goals here. One is perhaps the prosecution of some people, but there is also an accountability piece. The exposure of Russian tradecraft…educating the public.”

When Mr Mueller’s mission is seen in that way, the perils facing Mr Trump become clearer. For Mr Trump and his noisiest defenders in the Republican Party and in the conservative media are desperate to make this an argument about who is wicked, the president or Mrs Clinton.

But it is Mr Trump who remains consistently and inexplicably incurious about Russia, and whether it attacked American democracy. It is the president who calls the entire Russian investigation a hoax, fake news, and a witch hunt. He has scorned the findings of the intelligence agencies that now report to him that Russia did indeed interfere in the election, and with the clear aim of helping him to win. He presents the very idea of Russian collusion as a partisan Democratic conspiracy to call into question his victory. Even some Republicans cannot understand this strange refusal to criticise Russia and its strongman president, Vladimir Putin. In the words of Senator Lindsey Graham of South Carolina, a Republican foreign policy hawk, the Trump administration has “a blind spot on Russia that I still can’t figure out.”

A team without such a blind spot might want to know more about Mr Papadopoulos, not less. For the plea agreement that he has signed sets out in excruciating detail how Russian government officials and their semi-official envoys were eager, even desperate to cultivate the young man once they heard that he had joined the Trump campaign. One emailed to say: “we are all very excited by the possibility of a good relationship with Mr Trump.” A few days later the same connections told Mr Papadopoulos of the “dirt” they had obtained on Mrs Clinton.

Why were the Russians so keen on Mr Trump? Why was Mr Trump so keen on Mr Putin, saying many times that he wanted a better relationship with him? Why did Trump officials attending the Republican National Convention in the summer of 2016 water down a resolution calling on America to send arms to Ukrainians fighting Russian forces who had occupied part of their country? These and many other questions lie at the core of Mr Mueller’s mission. Hope that Mr Mueller is not fired before he completes his work. Keep sight of the task that matters—understanding an attack on America—through all the distractions that undoubtedly lie ahead.

Correction (October 31st, 2017): A previous version of this piece named the former campaign official indicted by Mr Mueller as Robert Gates. Mr Mueller indicted Richard Gates. This has been amended. Apologies.