calculations are on the mark

日本の真珠湾奇襲をルーズベルト大統領だけが「恥ずべき」とか「破廉恥」という形容詞で憤慨した背景についての個所の「国家の品格」の中の英文です。
It was only because the American people were steeped in the anti-war values of the Monroe Doctrine that President Roosevelt needed to make a display of anger and use extreme language like "infamous" and "dastardly." He made use of inflammatory rhetoric so that he could break his election pledge "not to spill one single drop of American blood abroad" and take America into the European war. His calculations were on the mark: the American people got into a lunatic fury, and Roosevelt was able to join in the world war.
原文の日本語を見るまでも無く "calculations were on the mark" が計算通りの意味であることは文脈から容易に分かりますが、この表現自体は初めて見ます。　 OneLookの検索では "on the mark" は次ぎの辞書の説明だけが見つかりました。
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs: Fig. right on the measurement point; showing just the right anount. It's exactly one quart, right on the mark.
考えて見ると "on the mark" とは反対の意味の "off the mark" は良く見かけますね。