The predictable word is in from Rio de Janeiro: failure. The conference 20 years on from the huge 1992 Earth Summit in Rio has been unable to produce even the pretense of an energetic verbal commitment of the world's community to sustainable principles.

The reason? These conferences have always been a fraud, lofted on excited green rhetoric and larded with ominous advisories that "this time we cannot afford to fail" and that "the tipping point" is finally here. But failure has been a loyal companion, and many a tipping point has tipped without amiss. There is no such thing as a world "community." There are rich nations and poor nations, and the former will never accede willingly to the agendas of the latter, however intricate the language of the final windy "declaration." The word "sustainable" has long been drained of all meaning.

The general absurdity of these Earth Summits — Rio, Kyoto, Copenhagen, Durban and now Rio again — is summed up in what the green forces hoped this time could be a concluding declaration to which enough nations could fix their name and declare victory for the planet. Originally, it was to be the commitment to a "green world" but not enough nations cared for that, so the fallback face-saver was a plan for a U.N. treaty to protect the international high seas.

To the greens' utter astonishment, early on Tuesday, it turned out that the U.S. and Venezuela were vetoing this plan. Whatever Hugo Chavez's motives, the reason for the U.S. veto was obvious and should have been from the moment the plan was mooted. The International Treaty on the Law of Sea was ratified in 1982, and the U.S. has always refused to sign it.

The Brazilians threw in the towel, insisting on a spineless final declaration. Like some Trollopian parson, somehow surviving the bureaucratic infighting was the Commission on Sustainable Development, which ...

The Latin American March for Education was called by the Chilean students' confederation, and demonstrations were held in Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, Uruguay and Venezuela. 

Some 10,000 protesters - according to the organisers - marched through the streets of Santiago once again demanding reforms of the educational system. And again, there was a crackdown by the anti-riot police, who arrested some 60 people. 

The demonstrations in other cities in the region were peaceful, with the exception of an incident in Bogotá, Colombia where the police fired tear gas.

"Today is a very special day because we are marching throughout Latin America," Esteban Miranda, president of the University of Chile law students centre, told IPS. 

He said the region-wide mobilisation was a demonstration of the similarity of demands by students in the region, as well as of the support for the movement in Chile.

"They are hanging in there with us, because we still have a long road ahead," the student leader said. 

José Barrera, a civil engineering student at the Catholic University, said that what is happening in Chile "is an example of what education is like when it's privatised, when it is no longer defended as a right of everyone." 

An education law enacted by the 1973-1990 dictatorship of General Augusto Pinochet set off a process of decentralisation and privatisation that gave private schools free rein to pursue profit and use entrance exams to select their students. 

The Chilean system is not just divided into paid private education and tuition-free public education, but is split into three: municipal schools run by local governments, which are publicly funded and free, state-subsidised private schools, and private schools that charge tuition.

Within the sphere of state-subsidised ...