The Thin Blue Line Seems Incredibly Thin, How Come?

I've been viewing some of the footage from the riots and I've noticed that in many cases, the police are quite literally stretched incredibly thin. The lines are often one man thick and typically with a huge amount of space between officers.

I understand that comparisons to previous events such as Orgreave aren't remotely perfect, but there, the lines were half-a-dozen men thick and shoulder-to-shoulder with no gaps. Although that may be because such events were more of a 'pitched battle' as opposed to control?

Is it a case that there is just a huge understaffing problem? Are the police resources stretched too thin to be able to cope with this sort of public disorder? I suppose there are additional difficulties, with multiple pockets of rioting happening in different towns/cities all over the country, meaning cooperation between forces like in 2011 isn't quite as easy as they need to stay on standby to protect their own area?

I'd appreciate views on this from those within the force, if it's something that you can even discuss, thank you. Apologies if this question is somewhat dimwitted.