When George Mitchell, the US president Barack Obama’s special envoy to the Middle East, sits down with the Israeli prime minister Benjamin Netanyahu on the sidelines of a summit in Paris tomorrow, there will be little fanfare – and that may suit Mr Mitchell. He has a reputation for being hard-nosed, but also for humility. He is discreet, understated and rarely departs from his boss’s game plan – virtues that a generation ago in America would have been associated with a “baseball man”.

It may seem of little importance to the Middle East peace process that when baseball ceased to exhibit even a pretence of being “America’s pastime”, and its biggest stars were suspected of using steroids, it was Mr Mitchell who was summoned to investigate it. But because he is so effective at parrying media questions and being the quiet man, his body of work – as chief negotiator in Northern Ireland, leader of the Democratic party in the US Senate, and most recently as lead investigator into drug abuse in baseball – is of particular relevance in providing a view into how Mr Mitchell will behave as negotiations become all the more contentious. And given this history, that it is he who will sit across from Mr Netanyahu tomorrow in Paris is a message in itself.

It is not just in the Middle East that Mr Mitchell has been asked to be an honest broker (and the phrase itself reveals that what he has to manage may not have been honest to start with). He has not served in positions where he is to be a steward of business as usual. Instead, his roles have given him an opportunity to confront and challenge entrenched interests.

Certainly, he has had plenty of other jobs to choose from. Had Bill Clinton had his way George Mitchell would currently be sitting on the US Supreme Court, but he refused the job that would have cemented his status as one the era’s great American statesman. While Mr Mitchell’s successes as a negotiator testify to his competence, the issues that he has chosen to tackle are a window into his consciousness.

By that measure, tackling drug abuse by millionaires who wave a wooden stick at a ball may seem a strange choice. But baseball is more than a game in America; it is an institution. The game’s special status is codified in the “antitrust” exemption it has from the US government, allowing it a leeway denied almost any other American enterprise, particularly in that it is protected as a monopoly and shielded from many of the regulatory demands of competition.

But often baseball’s exalted status has caused its owners to behave arrogantly and against the game’s interests. Rampant steroid abuse helped players to hit more home runs, brought fans back to the ballparks and helped to enrich both players and club owners for a decade. When suspicions emerged about the source of baseball’s new-found power, a game that was once a beacon of fair play, diligence and teamwork became synonymous with cheating. It became Mr Mitchell’s task to clarify what had happened, why it had happened and to prescribe remedies.

Certainly the stakes are much higher in the Middle East, but the dynamics are not so different. Israel has a special place in America’s diplomatic tradition. As President Obama has clearly pointed out, most directly in his address this month in Cairo: “This bond is unbreakable.” But Mr Obama has also conceded that sometimes the nature of this relationship had caused both parties to act against their own best interests. When running for the White House he noted that in America “there is a strain within the pro-Israel community that says unless you adopt an unwavering pro-Likud approach to Israel that you’re anti-Israel and that can’t be the measure of our friendship with Israel”.

Mr Netanyahu, the Likud party’s standard bearer, will meet Mr Mitchell at perhaps the most critical juncture in Mr Obama’s push for peace. While the president welcomed Bibi’s conditional acceptance of a Palestinian state last week, he mentioned nothing about how the Israeli premier held his ground on settlements in the West Bank. Just yesterday Mr Netanyahu said that “the more we spend time arguing about this, the more we waste time moving towards peace”. But in both the US secretary of state Hillary Clinton’s press conference with Avigdor Lieberman, and in Mr Mitchell’s press conference at the US state department last week, the US has held to its demand that settlements stop.

Someone has to bend. And it is unlikely that it will be Mr Mitchell, since he bears some responsibility for drawing this red line. As the lead author of the report by a fact-finding committee in 2001 on the causes of the al Aqsa intifada, Mr Mitchell wrote that “settlers and settlements in their midst” was an important cause of the uprising. He recommended that Israel “freeze all settlement activity, including the ‘natural growth’ of existing settlements”. He may be taking directions from Mr Obama, but it is many of Mr Mitchell’s recommendations that have become Mr Obama’s policy.

Mr Mitchell became well aware of the dangers of trying to hit too many home runs when he was investigating baseball. But he has shown, too, that he is not unwilling to swing for the fences when negotiations demand it. In April 1998, Mr Mitchell announced to all the parties engaged in peace talks in Northern Ireland that he was fed up with their quibbling over details that was endangering the treaty’s larger goals. He issued an ultimatum: if they did not settle the matter by the weekend he was returning to America for the Easter weekend, and would not return. The result of that gamble was the Good Friday Agreement.

Certainly he does not have as much power in this negotiating process. And he also doesn’t have as much time. Mr Mitchell had three years to forge a peace in Northern Ireland, and took 20 months to investigate baseball. The game of baseball may have no clock, but as Mr Mitchell meets Mr Netanyahu tomorrow he too must realise that time is of the essence.