warning graphic content .
shaun smith and jason collins were filmed on cctv assaulting two men .
the soldiers were drinking for hours before ` inexcusable ' attack last april .
they chased one victim round a tree and onto a main road to beat him .
despite brutal attack both were spared jail in ` exceptional ' sentencing .
they could have faced sentences of up to 10 years each for their crimes .
collins , 22 , has since been stationed to guard buckingham palace .