Why shouldn't the agents of the Afghanistan invasion not be insulted if you disapprove of it?

Isn't a bit hypocritical and incoherent to condemn the invasion of Afghanistan and then forbid Muslims from mounting insulting protests, eg

'Butchers return' and 'What are you dying for? £18k'.

Read more: http://www.dailymail.co.uk/news/article-1286784/Muslim-protesters-brand-war-heroes-murderers-homecoming-parade-turns-violent.html?ito=feeds-newsxml#ixzz0r1DK9VOO

against the agents of the invasion, ie British troops? I think British soldiers who die in Afghanistan should know that their sacrifices are not being appreciated.

In fact, they should go AWOL if they had any sense.  Why anyone would die for Bush, Blair, Brown and now Cameron and Clegg is absolutely beyond me.