For the past 72 hours, some of the most consequential diplomacy in the Middle East has taken place far from the cameras. Qatar, a gas-rich peninsula of fewer than three million people, has been working the phones and the back channels in an effort to stop a new round of American strikes on Iran from following Tuesday's midterm elections in the United States. The timing is no accident. American presidents have often been cautious about military action in the weeks before a vote, when a failed operation or a spike in oil prices could damage their party.

Once the ballots are counted, that restraint may weaken. Gulf officials appear to fear exactly this window: a period in which Washington is politically freer to act, and Tehran, feeling pressure, may be tempted to respond in kind. Qatar is an unusual broker because it holds contradictory assets. It hosts Al Udeid, the largest American air base in the region, yet it also shares the world's biggest gas field with Iran and has kept open lines to Tehran that many of its neighbours lack.

That dual position has made it a go-between before, from Afghanistan to prisoner exchanges. It also leaves Doha exposed. Any escalation would place both the American base and shared energy infrastructure within range of retaliation. The uncertainty has unsettled the whole Gulf.