Ideally, democratic politics is the "art of the possible" — the art of getting things done and governing a community in which diverse interests and perspectives exist. No one gets everything because everyone must be willing to negotiate and compromise. Some argue, though, that politics should be about achieving power and imposing control on others. This is an authoritarian position which is consistent with conservative religious ideologies in which no compromises on "God's Will" are accepted.
This perspective is best exemplified by the writings of Carl Schmitt, a German political philosopher whose ideas gained their strongest following in Nazi Germany. People motivated by Schmitt's understanding of politics today rarely come right out and admit it openly. They will participate in standard democratic politics as if they believed in its principles, but their long-term goal is to gain enough power to undermine the system entirely and replace it with a new system controlled by them. Although people with this agenda may lie about their goals, they can't entirely hide their true attitudes.
You can watch their rhetoric and behavior and see to what degree they truly believe in the importance of compromise and negotiated agreements. If instead they treat politics as an all-or-nothing contest in which they abandon every pretense at civility, rules, or the law in order to get what they want, then chances are they are closely following Schmitt's prescription. Is it coincidence that the people most like this in America today are Christian Nationalists and many of their neo-conservative allies in the Republican Party?
In Hitler's Justice: The Courts of the Third Reich, Ingo Muller writes:
Carl Schmitt — who can aptly be characterized as the "state thinker" of the Third Reich — was the first to make this polarized attitude of "friend or foe" respectable in scholarly circles. In 1927, in his book Der Bergriff des Politischen (The Concept of the Political), he expressed as no one else had how conservatives then understood politics.
In his view, "the specifically political decision on which political actions and motives are based" was "the distinction between friend and foe." Its purpose was to characterize "the most extreme degree of intensity in a connection or a separation," for a political foe is "precisely that other, that alien being, and it suffices to identify his nature to say that he is existentially an other, an alien in a particularly intensive sense, so that in extreme cases conflicts with him are possible which can be decided neither by a previously determined general norm nor by the verdict of a third party who is not involved and therefore impartial" -- that is, by neither law nor judicial decorum.
According to this doctrine, the concepts of "friend, foe, and struggle" acquire "their real significance through the fact that they exist in a framework of the real possibility of physical killing."
The ultimate aim of this sort of politics is to eliminate one's political opponents. If they cannot be eliminated by forcing them into a permanently subordinate role, they may legitimately be eliminated through physical extermination because the end goal of the political process is for one group or party to exercise complete control and dominance over the political system. There is no obvious or necessary reason for politics to function in this manner; it's simply the way politics naturally has to be according to adherents of this doctrine. The idea of pursuing a course of action for the sake of the community's good or best interests never even enters into the political calculations.
While Schmitt was writing secular political philosophy, in the long run his ideas have been preserved by religious nationalists. Conservative forms of religion, which tend towards authoritarianism, frequently espouse a Manichean theology of absolutes in which there is an absolute good is locked in battle with an absolute evil. Such a theology works well with a political ideology that conceives of politics in the same way. All that's necessary is to map one's political enemies with the absolute, evil enemies of God.
Liberal religion does not usually engage in such absolutes or Manichean theologies, so it's harder for it to work with a political ideology that runs along such lines. This is not to say, however, that the two are completely incompatible. Even liberal believers can espouse a "faith-based politics" which veers sharply towards Schmitt's political ideology because any sort of faith-based politics contains seeds of authoritarianism: feeling called by God to push a specific political agenda, feeling that God wills the imposition of a certain agenda and/or opposes other political policies, and believing that traditional religious categories can or should be fulfilled through the political process.
In America liberal believers have tended to follow a secular political course, pursuing secular political goals for secular political reasons. More recently, however, many more liberal believers have been promoting faith-based political doctrines which mirror those long espoused by conservative Christian Nationalists and which therefore are also more and more consistent with the political philosophy of Carl Schmitt: using the political process to establish the power of one's party or movement over all society to the exclusion of those who disagree and who can be more easily marginalized.
Political liberalism and liberal religion are in many ways incompatible with this conception of politics because liberalism tends to be more optimistic about human nature whereas Schmitt argued that "all genuine political theories presuppose man to be evil." Liberalism also tends to promote the idea of pluralism in society, but Schmitt rejected pluralism completely in favor of a single group or ideology dominating society both vertically and horizontally: from top to bottom in a strict authoritarian relationship and across all cultural, political, and social institutions.
