As polling day in America begins on Tuesday, The Economist’s forecast model suggests that the presidential contest is agonisingly close. Kamala Harris narrowly moved ahead of Donald Trump this morning. If the polls are even slightly wrong, one of them could win a decisive electoral-college victory.

How quickly the results will be known will depend in part on how large is the winning candidate’s margin of victory. The first states to be called, based on exit polls, will be where one candidate is far ahead. A better early indicator of the overall result will be changes in county-level tallies since 2020: these will appear live on our results page throughout election night. The race will probably depend on seven swing states. Of these, Georgia and Michigan may be fastest to count; Pennsylvania, the likely pivotal state, will probably be slower. It will not start processing postal ballots until Tuesday morning.

The prospect of a divided Congress—and with it the shelving of much of the next president’s agenda—looms large in America’s election. Our forecast model gives the Republicans a 71% chance of taking the Senate. To retain control, Democrats cannot afford to lose Arizona, Michigan, Montana, Nevada, Ohio, Pennsylvania or Wisconsin. Yet their incumbents in the largely red states of Ohio and Montana look particularly vulnerable. They could withstand a loss if they flipped a seat elsewhere, and some recent surveys have put the challengers to Republican senators in the pale-red states of Florida and Texas just a few points behind them. But our model only gives Democrats a one-in-five chance of flipping seats in either state.

Meanwhile the battle for the House is a coin-toss. California is a key battleground. If Democrats can flip five Republican-held districts in the blue state, they may well take the lower chamber. That will be another nail-biting race that adds to the uncertainty on election day.

China’s government hosts endless forums, summits and expos each year. But the China International Import Expo has special significance to the ruling Communist Party. The country’s main economic contribution to the world has been in the form of exports. An import expo—one in which thousands of foreign companies advertise their wares to local consumers—intends to show that China is more than a giant factory. It is a country of increasingly wealthy consumers, too.

The event, which started on Tuesday, will attract all manner of multinational groups, hoping to get a small share of China’s market . But the domestic demand that China’s rulers are so eager to display is flagging. Imports rose only 0.3% year on year in dollar terms in September. That is hurting international brands. LVMH, a luxury group, recently attributed poor quarterly results to “deteriorating trends from the Chinese customer”. Expos alone will not improve local consumer sentiment.

On Tuesday the presidents of Azerbaijan, Kazakhstan, Kyrgyzstan, Turkey and Uzbekistan will discuss prospects for economic integration at a summit of the Organization of Turkic States in Bishkek, the Kyrgyzstani capital. Once a talking shop, the OTS is turning into a vehicle for regional co-operation. The war in Ukraine has damaged Central Asian countries’ trust in Russia. Many of the group’s members see the OTS as a way of reducing dependence on the Kremlin.

Turkey, the biggest of the OTS countries, has taken note. Turkish developers have signed contracts worth tens of billions of dollars across Central Asia. Turkey’s arms companies are busy in the region, too. Azerbaijan, Uzbekistan, Kyrgyzstan and Turkmenistan (the latter an OTS observer) have already bought Turkey’s battle-tested Bayraktar drones. Kazakhstan is in talks to produce them. Russia maintains economic and political sway in the region. But Central Asian officials now talk of pursuing a “multi-vector” foreign policy and believe time is on their side.

The photographs are lighthearted. A woman in a colourful dress leans against a car in London; a boy pushing a bike grins at the camera; two friends pose on New York’s subway. “As We Rise”, an exhibition which opens at the Saatchi Gallery in London on Tuesday, brings together more than 100 such images to explore “black identity on both sides of the Atlantic”. From Britain to Canada to the Caribbean, the images capture everyday interactions in the 20th and 21st centuries. The photographers featured include Sir Horace Ové, a Trinidadian-born British artist who died last year, and Arielle Bobb-Willis, an up-and-coming American talent.

Since the mid-19th century, black photographers have documented the spirit of their communities. They have countered centuries of stereotypes and clichéd representations. This exhibition has a mix of family pictures, artsy shots and self-portraits. It is both a historical archive of the African diaspora and a testament to the joy of good photography.