First, geography. Belfast is a city of flashpoints where loyalists and republican areas run up against each other – or are simply flashpoint areas in times of tension.

In loyalist Belfast: Sandy Row in the city centre, the Shankill Road district out west, the Antrim Road to the north, and Newtownards Rd to the east.

Now, the money – the economics. When you have known a little bit about these areas down the years, you know there’s not a great deal to distinguish them. They are all basically urban, working-class, post-industrial areas, once reliant on the shipbuilding and linen that put Belfast on the industrial world map.

In short, not a lot to choose between them.

So why is it that east Belfast should be the area of violence over the past month? Not solely, it’s true – but it’s the scene of by far the most trouble.

There are two factors that are critical.

First the UVF. The names are well-known, as is the belief that to some degree the loyalist paramilitary grouping is something of a renegade operation in the east.

The chief constable pointed to individuals from the UVF being involved in trouble on the streets. He also said the organisation as a whole is not directly involved – just its people in that area.

Specifically, it’s believed they are ensuring people gather at certain times in certain places and chuck a certain amount of petrol bombs and other objects at the riot police.

Chief Constable Matt Baggott has said: “Senior members of the UVF in east Belfast as individuals have been increasingly orchestrating some of this violence – that is utterly unacceptable and is being done for their own selfish motives.”

The second defining characteristic in the east is politics – specifically, a leaflet unionist parties put out blaming East Belfast MP Naomi Long for the flags issue. She is the Alliance MP who unseated the DUP’s Peter Robinson for this key loyalist seat.

As an MP – not city councillor – she had little at all to do with the council’s decision to limit the days the union flag flies over city hall. But she was fingered because her Alliance party held the balance of power which pushed the vote through city hall.

That was enough. Anything to get her out, reasoned unionists. Others say this was incendiary and lit the touch paper for trouble in the east. Peter Robinson, for one, has had to ask those on the streets to desist.

Of course, alienation from politics plays a part in loyalism, as it does in republican areas. Both sides get attacked by each other.

But in the east it is politics and paramilitaries as nowhere else.

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