By Nick Caistor
Latin America analyst
Supporters of both sides in the conflict have taken to the streets
When the ousted president of Honduras, Manuel Zelaya, won a narrow victory as leader of the Liberal Party and took office in January 2006, few Hondurans expected radical changes in their country.
The Liberal Party is a traditional left-of-centre grouping which has alternated in power with the National Party since the return of civilian rule in 1981.
Both parties have tried to reinforce civilian democracy after more than a century when the armed forces were the dominant force in Honduran politics.
Both have been accused of doing too little, and of tolerating widespread corruption in one of the poorest countries in the western hemisphere.
But President Zelaya took his opponents and his supporters by surprise.
As soon as he came to power, he started taking Honduras to the left.
An early symbolic act was the restoration of diplomatic ties with communist Cuba for the first time since 1962.
On a more practical level, he signed Honduras up for Petrocaribe, the agreement by which oil-rich Venezuela sells oil to poorer countries in the region.
Manuel Zelaya does not enjoy a widespread power base in Honduras
Mr Zelaya also announced Honduras would join Alba, the Venezuelan-inspired trade and finance agreement intended as an alternative to the free trade agreements backed by the United States.
At the same time, he began to adopt a more independent line with regard to the US, traditionally the dominant external influence on Honduras.
Occasionally this effort descended into farce. In March 2008, when the US Food and Drug Administration banned imports of Honduran melons, President Zelaya went on national TV biting into a locally grown one, complaining of US "injustice".
He later joined Bolivia and Venezuela in protesting about US interference in their countries, and for a while refused to accept a US ambassador.
Although these moves won the president the backing of some trade unions and left-wing groups in Honduras, they caused serious rifts within his own Liberal Party.
With the countdown to the presidential elections this November, these splits became a crisis.
In Venezuela, Argentina and other Latin American countries, incumbent presidents have sought to change the national constitutions to give them the possibility to serve a second consecutive term in office.
Presidents have argued that, in the modern world, it is necessary to have continuity over more than four years if effective policies for change are to be pushed through.
President Zelaya pushed to hold a vote asking the Honduran electorate whether they were in favour of constitutional reforms by setting up a constituent assembly.
The Supreme Court declared such a vote illegal and in violation of the constitution.
When Mr Zelaya pressed on with his plans to hold the vote on 28 June - seen by his critics as a move to end the current one-term limit on serving as president - the scene was set for a showdown.
The military moved in to arrest him and fly him out of the country. The leader of Congress, Roberto Micheletti, was subsequently sworn in as interim president.
Roberto Micheletti insists his government is legal
Mr Micheletti had always been a rival of Mr Zelaya's within the Liberal Party, and the two men clashed again when Mr Micheletti stood in the Liberal Party primary for the November elections.
Mr Micheletti and his followers, including the armed forces, have argued that Mr Zelaya overstepped the constitutional provisions, acting illegally by seeking to call a referendum on his own authority.
Unfortunately for President Zelaya, he has not succeeded in creating a power base within Honduran society that will defend him on the streets or in Congress.
In Venezuela, President Hugo Chavez was an ex-army officer who spent several years gathering support before embarking on his programme of radical change, which he put to the electorate at every stage.
Similarly in Honduras's neighbour, El Salvador, where the left-wing FMLN won the presidency in 2008, the former guerrilla grouping has worked at a grassroots level for many years to convince voters they are a responsible democratic party that will only bring in change gradually and by consensus.
In Nicaragua, Honduras's southern neighbour, the former revolutionary Sandinista party managed to maintain support in trade unions, popular groups and the armed forces after being voted out of power in 1989.
This has meant that President Daniel Ortega, the revolutionary leader who was re-elected in November 2006, has a much more solid backing for his modest reform proposals.
Manuel Zelaya has had none of this kind of support. There appear to be no factions among the armed forces who back him - a crucial factor in Venezuela when President Chavez was briefly deposed in 2002, but reinstated thanks to military backing.
Because of the years of repression and timid civilian government, the trade unions and other left-wing social pressure groups are weak in Honduras.
During his three and a half years in office, President Zelaya has not succeeded in building them into a force that would risk their lives to support him.
Nor are ordinary Honduran citizens likely to protest or to boycott any new regime for long. According to opinion polls in 2009, Mr Zelaya enjoyed only around 25% of popular approval.
It seems that the best the ousted president can hope for is sufficient pressure from the international community to allow him to finish his term in some guise or other.
But "Zelayismo" is not likely to enjoy any prolonged future beyond then.