WITH its long bulk of purple volcanic stone, the National Palace is not just any building. It looks out onto the Zócalo, the teeming heart of Mexico City, peopled by the dark-skinned Mexico that travels by bus or metro rather than in big SUVs with darkened windows. Tourists file in to the palace to see the murals by Diego Rivera. A less-visited corner houses the modest set of rooms where Benito Juárez, a 19th-century president, lived and died, having tackled the power of the Catholic church and defeated a French invasion.

So when Andrés Manuel López Obrador declared that he would be the first Mexican president since 1910 to use the palace as his workplace, he was making a statement that was both political and historical. Mr López Obrador (known as AMLO to Mexicans), who won a landslide victory in a presidential election on July 1st, promises a “fourth transformation”, after those of political independence, Juárez’s assertion of national sovereignty and the revolution in 1910-17. “This is a change of regime, not just of government,” says Lorenzo Meyer, a historian sympathetic to AMLO.

Although he does not take office until December 1st, some of the contours of this change are already clear. Those who compare AMLO either to Venezuela’s late Hugo Chávez, an authoritarian populist, or Brazil’s Lula, a corporatist social democrat, are missing the point. Mr López Obrador is steeped in a particular version of Mexican history (about which he has written several books), from which he derives his inspirations and world-view.

His first hero is Juárez, a liberal but one in whom the new president sees a leader who “proposed a new Mexico based on honesty and republican values”, according to José Agustín Ortiz Pinchetti, AMLO’s authorised biographer. Second is Lázaro Cárdenas, who in the 1930s nationalised the oil industry and carried out a state-controlled agrarian reform. He stands, as Mr Meyer puts it, “for bringing social justice to a society that still has colonial characteristics”, of racism for example. Much as the new president hates Mexico’s democratising “neoliberal” governments since the 1980s, which he (questionably) equates with the pre-revolutionary dictatorship of Porfirio Díaz, his nationalism has a strong streak of pragmatism.

What all this means is that AMLO will be economically moderate, socially bold and politically centralising— but not necessarily democratic. On the economy, he is committed to fiscal responsibility and has promised not to raise taxes for three years. He seems to be backing away from campaign promises to reverse private investment in energy and halt a new airport for Mexico City.

He thinks he can fund a big increase in public investment, mainly for transport projects in the poorer south, by eliminating waste. The first law approved by the new congress (in which AMLO has a majority) involves a swingeing cut in the salaries of senior officials. Federal “delegates” will police spending by state governors. He plans a shake-up of social programmes. “We think we can re-direct $15bn-17.5bn” to a universal non-contributory pension and a scheme to help 2.6m unemployed young people back into school or into jobs, says Gerardo Esquivel, who will be a deputy finance minister.

Much of this is laudable in principle. In practice, there is a risk that the salary cuts deprive AMLO of the necessary expertise to run a complex state. The infrastructure plans have not been properly costed. The same air of improvisation hangs over plans for public security, a crucial issue.

Like Juárez, AMLO is personally austere. His recipe for fighting corruption and crime seems to be to restore the authority of the federal government. That may well be popular. Historically, Mexico has floundered when power is dispersed. But the president’s “delegates” look to some like a device to turn his Morena movement into a party of the state. AMLO mistrusts “civil society”, the pressure groups that call for stronger checks and balances. Even some of his supporters worry that his aim may be to strengthen the state rather than democracy.

No Mexican politician knows his people, or at least the poorer part of it, better. As a young man he spent six years living in a hut with the Chontal Indians. During his campaigns he has visited each of the 2,500 municipalities in Mexico twice, according to Mr Ortiz. He is an effective political communicator. But his vision of history may not accord with a country which many Mexicans do not think is still “colonial”, but who voted for him out of despair at crime and corruption. It is still unclear whether Mexico wants a change of regime, or just of government.