By Daniel Schweimler
BBC News, Santa Cruz, eastern Bolivia
Feelings are running high over the new constitution
Bolivia is a country divided - between rich and poor, between indigenous and non-indigenous, between east and west.
It's been that way for much of the past 500 years but there are hopes among many there that all that is about to change.
The large, poor and indigenous population is resting those hopes on Evo Morales, the country's first indigenous leader, and his proposed new constitution that would radically alter the way the poorest country in South America is run.
Bolivians will vote on the constitution on 24 January and, nationwide, it is likely to be approved.
But it faces strong, sometimes violent, opposition in the east of Bolivia, where many have called for more autonomy from central government - and some for outright independence.
Campaigning is underway and, as the day of the vote approaches, tension is increasing.
The government in La Paz says that the wealthy landowners who run the east of Bolivia like a personal fiefdom simply do not want to share their oil and natural gas wealth with the the poorer, indigenous majority.
But many in the east say Mr Morales is a puppet of the controversial Venezuelan leader, Hugo Chavez, and is trying to impose his brand of indigenous socialism on them.
American writer and analyst Jim Shultz has been living and working in Bolivia for more than 10 years and has observed how the issue of autonomy has developed.
By campaigning for autonomy, the people in the east are trying to avoid dealing with President Morales's government, he says.
"They're saying 'we don't want him to have control of our natural resources. We don't want to share our mineral wealth, which by luck of geology happens to be under our feet. We don't want land reform.'
"'We don't want any of the things that Evo Morales and the majority of the people in this country stand for. So autonomy is our way of excluding them.' Autonomy is the equivalent of a gated community in politics."
Portugal Quispe is a community leader in the indigenous enclave in the city of Santa Cruz known as Plan 3000.
He operates from a building called the House of the People, a kind of unofficial town hall.
There were violent clashes there earlier this year when the governing elite in Santa Cruz called protest strikes against the reforms of President Morales.
When the people of Plan 3000 refused to strike, says Mr Quispe, the response was swift and brutal.
"We are constantly threatened," he said. "They are racist. They call us collas - Indians. An Indian, a colla, can't go to the main plaza. If we do, they'll beat us.
"Because we didn't participate in the strike, they sent paid thugs out, five, six, seven trucks, armed with sticks, to close the businesses, to paralyse Plan 3000, to stop people working. So we resisted, we organised ourselves," said Mr Quispe.
When analysts in Bolivia talk about who really runs the east of the country, the same name always crops up: Branco Marinkovich.
He is a multi-millionaire businessman who heads the Pro-Santa Cruz committee, a non-elected movement of local landowners and businessmen.
Mr Marinkovic insists that he leads a civic movement which promotes the best interests of Santa Cruz and all its people.
And he is equally emphatic that it is the government, and not his organisation, which has provoked confrontation with its proposals for constitutional reform.
"We haven't killed people in Santa Cruz," said Mr Marinkovich. "It has been proved that it is the government which encouraged violence. They have paid people…. We are not to blame. The violence we have been suffering for the last four years, was all generated by Evo Morales."
"To begin with," he added, "the dialogue hasn't solved anything. We won't just have fighting, but general chaos, as the new constitution will not work.
"It has many contradictory articles, 300-400 articles, it's mad. A constitution should be simple. But this will bring a great economic-political crisis in Bolivia. It'll be a very deep crisis."
The Bolivian government and indigenous groups in Santa Cruz say that the violent wing of the Pro-Santa Cruz Committee is the Union of Santa Cruz Youth, or UJC.
I asked the UJC vice-president, Victor Hugo Rojas whether he thought more violence was inevitable in the run-up to the January vote on the constitution.
"Change," he said, "is painful. Whether the change will benefit them or us, we'll have to see, but there will be violence. It has to happen and may get worse."
"We've always defended ourselves with marches," said Mr Rojas. "And if we've had to defend ourselves in any conflict it's always been with sticks and stones, nothing more.
The difference, he said, is that the other side were using firearms "without any reason or shame".
"And they're being supplied by Venezuela and Cuba. They're getting military training," he alleged. "We don't get any of that."
The violence that flared up in August and September was not confined to Santa Cruz. In the north-eastern department of Pando, at least 30 peasant farmers, on their way home from a pro-government rally, were ambushed and killed.
Plan 3000 has seen clashes between Morales' supporters and opponents
A report by the South American regional body, Unasur, called the attack a massacre and a crime against humanity. The opposition in the east said the report was financed by the Cuban and Venezuelan governments.
The regional governor in Pando, Leopoldo Fernandez - who is vehemently opposed to the government's reform plans - was arrested, accused of being behind the killings.
President Morales promises better times for what has long been one of the poorest and most volatile countries in the region, with proposed changes including:
- A greater say in the running of the country for the indigenous community, the poor and for women
- Better land distribution
- Foreign investors paying a greater share of their profits to the Bolivian people.
These are fundamental changes. And with changes of this magnitude, with so many hoping to gain, others fear that they are going to lose.
Bolivia's turmoil is not over yet.
Assignment is broadcast on BBC World Service on Friday December at 0006 GMT, Saturday at 0606 GMT and Sunday 1306 GMT.