This is how I see it:
In countries where a dictatorship or junta system of government exists, we applaud as we watch crowds of revolutionaries voice their anger at their governments by toppling statues of tyrants or storming palaces of corruption. They have symbols of power on which to focus their anger, and on which to wreak their destruction...and what do we have? What does England have? What does America have? We live in democracies under capitalist systems of government - where are our idols, our monuments, our great palaces of corruption? Our symbols are the every-day...shops and banks and economic powerhouses. And so, when our people rise up in revolution and find that their anger cannot be contained anymore, certain factions will begin to smash and destroy these capitalist monuments. It's the only place that truly makes sense, raised (indoctrinated) as we all are a system of government that demands that we consume, that we spend, that we keep the economic bubbles inflating and bursting, inflating and bursting, forever more. And then they wonder why, when people who have been oppressed and degraded for far too long rise up, it's the big shiny expensive stuff that they have told us time and again represents our value in society that are the first to go. This form of government tells you that you are nothing f you don't have the latest iPhone, most unique (expensive) runners, seasonal/yearly changes to your wardrobe, skincare products to keep you pretty, gym membership to keep you buff, huge mortgage on a massive house, new car every year...the list goes on, and the common denominator is money. Those at the top have it, those at the bottom don't. The indignities keep getting heaped upon you - student debt, no access to college or university, low standards of education, the poverty trap, job-bridge and unpaid internships instead of work, apprenticeships closing doors, unskilled labour becoming the only option, depression, anxiety...anger. You can't quite grasp why it is life seems so much more difficult for you, that you can't attain the markers of success (all consumer driven), that justice doesn't operate for you the way it does for others, and that the odds are always stacked against you everywhere you turn.
When you're not well educated, and you can't express this anger in beautiful words that will sway, then by this reasoning your anger doesn't have validation. Hence during the England/London riots in 2011 the news stations continuously broadcasted interviews with young men (usually of colour, but certainly of lower socio-economic classes) who were either angry at 'the government', but couldn't explain their anger any further than that, or were laughing about how they had just robbed some great gear. Either way the point was to reduce the reasons behind the riots to something other than what it was - unjust treatment of the people at the bottom. Instead we could all sit in our sittingrooms focusing on how animalistic the riotors were, how they were just looting, how they didn't even know what they were at and were just following the crowd, how they're social welfare wasters who just had nothing better to do. Then we can comfortably switch channels, safe in the knowledge that those who are rioting will swiftly fade away because they don't really have anything to hold them together.
Which is, of course, exactly why they don't hold together. Those on the outside will sit back and allow police to swarm in using any measure of force, we'll allow national guard and military intervention, we'll allow the prisons to fill up with uneducated, young, economically nonviable men and women. And the wheel will keep on turning. The shops will be fixed, we'll all go back to consuming, but there will be a nagging feeling that something isn't quite right. And the anger won't go away, it'll just stay beneath the surface, waiting for an opportunity to show itself again. This has happened in every country in the world; this happened in Ireland, in England, and it's happening in Ferguson and all over America right now.
Those who riot instead of peacefully protesting don't negate the reasons for the protest, despite what the media would have us believe. Let's face it, that would be the easier thing to swallow - we wouldn't have to question our government, or take a hard look at our own privileged position in society and how precariously it's built on the subjugation of others. It's the same for those at the other end of this spectrum, the ones screaming in the streets to be heard, but their voices are so deformed by anger and terror that they can't form the right words.
Just because somebody can't tell you why they are angry does not mean that they don't have a right to be angry.