Defending 'the region'

I write to make a further contribution to the ongoing debate about Australias strategic place as a Top 20 power. In Peters latest response he implies that regionalists are less grown up than globalists. I beg to differ. Peter talks about defending a broadly-defined set of global interests. But those interests are ill-defined: how broad is broad enough? And, if its appropriate, how much should we contribute to the fight in Iraq and Syria in order to win, rather than just to keep the fight going. Contemplating an approach involving piling on with more is frightening, with dark consequences.