Even if the cardassians had not joined the dominion, or the founders sowed dissent between cardassia and the klingons there is a chance thay they may have fallen back on their old behaviour.
From the moment they signed the armistice back in 2367 the cardassians were already prepping for another war. In 'the wounded' they were using a science station as a weapons supply depot. this station was within striking distance on 3 federation sectors. despite the protests of innocence by the cardassians, picard knew that it was true and in the 'interests of peace' did nothing about it apart from telling the cardassians the federation would be 'watching'. then in 2369 the cardassians had another military build up in mcallister nebula with the intention of a surprise attack on minos korva, a federation world. the federation again let this incident slide.
the cardassians clearly didn't give a shit about the peace treaty, yet the federation was bending over backwards to appease them.