From California to New York, the tide of protest keeps rising

What started last month with a lofty promise to "Occupy Wall Street" and a sit-in at a public park in Manhattan's financial district has spread into a national protest movement with miniature demonstrations popping up in cities from Los Angeles to Boston.

Organised on social networks such as Twitter, and galvanised by anger at the arrest of 700 protesters in New York at the weekend, activists are erecting tent cities and planning marches on banks, corporate headquarters and police stations across the US, in an effort that idealists among them hope might grow to upend politics.

The range of participants' complaints is as broad as the protest itself, and the absence of specific demands has prompted derision in some quarters, but the movement is coalescing around the view that the country's politics and its economy are skewed in favour of the moneyed elite.

As Occupy Wall Street has been joined by Occupy Philadelphia, Occupy Chicago and more than a dozen other copycats, the unifying mantra of the protesters has been that "we are the 99 per cent" – ordinary Americans frozen out of the economic gains of the pre-recession era, disproportionately hurt by the downturn, and routinely ignored on political issues ranging from education to the environment to war.

"Our beautiful system of American checks and balances has been thoroughly trashed by the influence of banks and big finance that have made it impossible for the people to speak," Harvard University doctoral student Marisa Engerstrom told reporters as she took part with hundreds of others in a march on Boston's State House, calling for an end to corporate influence on government.

More than 1,000 people are now living under canvas in makeshift camps in major cities, and promising to stay through the winter. In New York's Zuccotti Park, a stone's throw from the statue of a bull which is the informal symbol of Wall Street, the protest camp is now 19 days old. Fuelled by donations of money and pizza from passers-by and from across the country, protesters have set up feeding stations and an elaborate system for developing the rules of the community.

It has become a gleeful celebration of the modern art of protest, with often humourous placards strewn around the site and, on one occasion, demonstrators dressed as zombies lurching across the road to picket the New York Stock Exchange. Music and drumming reverberate around the camp through the day, and the site has its own newspaper, The Occupied Wall Street Journal. There is the occasional drop-in by a left-wing celebrity, too. Participants use cameras and laptops to spread details of the protest on the internet.

For the first two weeks Occupy Wall Street's nebulous leadership expressed disappointment that the media was ignoring its protest, although editors said they gave it coverage proportionate to its size. Now, though, spirits have been lifted by a real sense of a movement developing. When protesters flooded on to New York's Brooklyn Bridge on Saturday, resulting in 700 arrests, the protests became national news.

In New Orleans, activists plan to march on the Federal Reserve. A camp sprang up in Los Angeles for the first time on Saturday and has been growing in size. In San Francisco, 200 supporters surrounded the Bank of America building in the city's financial district, and mayoral candidate John Avalos spoke to the crowd, saying: "This building right here is a symbol of the incredible greed and wealth that has accumulated into fewer and fewer hands."