"Whose tweets? Our tweets!" Sometimes, only puns will do.

The Brookfield Winter Garden is the sort of aggressively bland corporate un-place where scuffles with the NYPD are not supposed to happen.

The financial district of New York is full of spaces like this: soulless private-public atriums full of force-grown unseasonal greenery, glistening 1980s marble and glaze-eyed commuters on their way to meetings. It's a place for "passive recreation" -- the stated function of Zucotti Park, also owned and run by Brookfield industries.

Absolutely nothing of emotional or political significance is ever supposed to happen here, ever. Right now, though, scores of members of the police force Mayor Bloomberg called his "private army" are arresting people seemingly at random just for looking like they might be working against the world's largest investment bank, rather than for it.

Just after eight in the morning, several hundred protesters from Occupy Wall Street had gathered in front of the headquarters of Goldman Sachs, banging drums, blearily slurping coffee and carrying a large, wobbly papier-mache squid. The latter was a reference to Rolling Stone journalist Matt Taibbi's iconic denotion of the bank as "a great vampire squid wrapped around the face of humanity, relentlessly jamming its blood funnel into anything that smells like money".

Some of the protesters also wore homemade cardboard squid hats. Yeah, take that, everyone who used to be skeptical about radical writers' ability to change the world using only the power of humorous metaphor.

Black bloc it wasn't. But this wasn't New York's day of action, not really. The demonstration was called in solidarity with the workers and occupiers attempting to block major ports along the West Coast of America, many of which happen to be controlled by subsidiaries of the Goldman group. Which also owns much of America's university system. And the shipping industry. And your mortgage. And your soul.

The fact that angry chanting and heavy policing have become routine features of life in the financial district is perhaps only appropriate in a country where four million families have been made homeless by a banking industry that was recently rewarded for trashing the economy with trillions of dollars of public money.

After a noisily peaceful march around the Goldman building, which entirely failed to collapse like the walls of Jericho, some of the protesters broke off to march through the World Financial Centre, adjoining the Winter Garden Plaza. Which is when the police freaked the hell out.

Red-eyed, astonished businesspersons held up their smartphones like protective talismans as emissaries of the 99 per cent danced around the ornamental ferns. Police poured in as someone dropped a West Coast Solidarity banner above the escalators. Protesters stood and shouted "everybody pays their tax, everyone but Goldman Sachs" -- well, close enough, the company paid only one per cent tax in 2008 -- just a little too long. On the turn of a penny, the arrests began.

By now we're used to hearing about protesters being arrested for taking part in peaceful actions, but this is the first time I've truly witness young people being grabbed at random just for standing near a demonstration with a phone or camera.

At least two of the 18 arrestees were journalists, including Radio Dispatch's John Knefel, and it is pure luck that the officer who shoved me through the atrium doors, shouting "your turn now", when he saw me tweeting, did not decide to arrest me too. As citizen journalists and members of the marching band sat in the back of the police van, a chant started: "Whose tweets? Our tweets!"

In the face of this sort of paranoid over-protection of a degenerate financial elite, you have to pun, because otherwise you might put your fist through a wall.

Funnily enough, last week, when hundreds of protesters and local campaigners really did take over a foreclosed property in East New York technically belonging to Bank of America, Bloomberg's army was almost nowhere to be seen.