Any survey of American political discourse will quickly how widespread and powerful fear is as a motivation. An enemy is identified( a nation, ideology, statistic, legislative bill, etc.) and people are taught to fear this enemy because it threatens an accepted common good (democracy, freedom, the elderly, world peace, life as we know it, etc.). Once a fear is created, politicians try as hard as they can to attach their opponents to to that fear.
In health care we either fear "death panels," socialism, and the loss of individual autonomy, or we fear insurance companies that exploit the little guy. In environmentalism we either fear no less than the end of the world or the collapse of the economy. In national security, we fear Islam/terrorism/Osama bin Ladin, fascism, and nuclear weapons. In nominees for the Supreme Court, we either fear the overturn of Roe v. Wade or activists judges who will publicly burn the Constitution. In economic debate, we fear losing our jobs - especially to foreigners. On ethical issues, we either fear the moral and religious decline of Western Civilization or we fear a rebirth of Nazism (a point recently made on an episode of "Family Guy").
Whether left or right, the trend is the same: people are manipulated into fearing the opponent as the harbinger of the apocalypse in order to win an election (see also: "Daisy") or pass legislation. If people fear that an accepted common good of society is threatened, they will fight tooth and nail to preserve their way of life. Each policy and politician promises they they can assuage our fears, while simultaneously provoking them. In the end, such promises are found to be empty as one fear gives way to a new fear.
Consequently, within Christianity it is right to debate how we understand the common good (Does the Bible affirm our values of individual autonomy, freedom, or inalienable rights? What does the Bible say about creation and the environment? etc.) It is right to debate the various means by which those goals are to be accomplished. But it seems to me that all use of fear as a motivational tool is directly contrary to the heart of the Gospel and thoroughly un-Christian.
As I understand it, Christianity is vehemently opposed to fear. In fact, Christianity is the true solution to fear. While the fearful "turn or burn" sermon never seems go away, it is not the good news of Jesus. As St. Paul says "you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, 'Abba! Father!'" (Romans 8:15). Or as St. John says, "There is no fear in love, but perfect love casts out fear. For fear has to do with punishment, and whoever fears has not been perfected in love. We love because He first loved us" (1 John 4:18). Since we have now peace with the Father we have nothing to fear. Since we are loved unconditionally by God, we are free from the fear that drives political discourse and can live (and vote) confidently in love.