This paper argues that a major cause of war in a brinkmanship crisis is not the misperception of the adversary's response, but rather a situation where leaders are compelled to act because of domestic threats to their power. A comparison of the brinkmanship crises of the Beagle and the Malvinas show that the prospect of war was critically affected by environmental conditions (such as the survival of the regime) under which decision makers operated. These conditions placed strong external constraints on the initiators that affected their judgment and the way they managed the crises. Where the conditions were less severe, as in the Beagle case, the leaders could retreat from the warpath. In the Malvinas case, the leaders confronted a no-win situation and the outcome was war with Great Britain.