The difference is that at bloody Sunday teerorosts were seen in the crowd with weapons. This does not make what went on afterwards right but guilt can be pointed at both sides.

Manchester was filled with innocent shoppers going about a normal unpoliticised day when these cowards chose to attack in an attempt to kill and maim many people. Manchester and the proud people of this city have subsequently shown that terrorist scum will not win. They failed on attaining their goal that day and we have got stronger.