R. Jonathan Sacks, One People? Tradition, Modernity, and Jewish Unity, pp. 88-89:
[B]y the end of the nineteenth century Reform and secular Zionism were powerful forces, and Orthodoxy was bound to part company with both.
But there were profound divisions within Orthodoxy itself. There were movements to hold together what secularization was dividing apart: Torah and secular culture, Judaism and Zionism, and the Jewish people. Paradoxically these three movements -- torah im derekh eretz, religious Zionism, and communally involved (Gemeinde) Orthodoxy -- have often been grouped together under the name 'Modern Orthodoxy'. Strictly speaking, however, they were the opposite, for they were an attempt to go against the grain of modernity. Contemporary culture replaces the traditional 'and' with a distinctive 'or': Torah or secular culture, Judaism or Zionism, Orthodoxy or the Jewish people as a whole. In each case religious principle suggested that the former must take precedence over the latter. So modernity favored those branches of Orthodoxy that made the choice, rather than those that resisted it. While in principle they retained their commitment to derekh eretz, the return to Zion, and Jewish unity, in practice the full implications of these tenets were neutralized. So the cluster of attitufes associated with secessionist Orthodoxy -- rejection of secular culture, an attitude of detachment towards the State of Israel, and a refusal to engage in joint action with the non-Orthodox -- has prevailed. Modernity has been hostile to 'Modern Orthodoxy'.