It's easy to get caught up in condemning the current -vehicle- of bigotry, and in the most general terms, whether it be religion, patriotism, nationalism, ethnocentrism, or whatever else you care to mention. You can also get caught up in demographics, defining humanity down into discrete groups, slicing up the population in a false and misguided effort to isolate "homogenous" sectors for blame or approbation. Pitting such loosely-defined groups against one another on any given issue generates a lot of heat, but very little light. Both lead to error and both are impractical--I'll try to explain why I believe that's the case.
1. The road to mass bigotry is universalAsian, white, black, male, female, young, old--whatever the demographic, mass bigotry is generated in the same way, for all peoples, and for all of history. Social leaders appeal to an edifice of authority to exploit popular ignorance of a certain group. This is done as a means to some end the leaders have in mind. The edifice of authority may be religion, as in the case of prop 8. It may be nationalism, as in the case of Nazi Germany or Stalin's Russia or Pol Pot's Cambodia. It may be patriotism, as in the case of Bush's America. The only thing shared among those creeds generally is that they are all edifices of authority, they are tools, means for generating social solidarity.
2. These nebulous edifices of authority do not inherently cause bigotryThey can undeniably be used for such purposes, true. But they also are used for noble, humanistic and just purposes. Martin Luther King Jr. constantly appealed to religion to promote his quest for justice. Gandhi likewise did so for the causes of peace and tolerance. The council of nuns that battled Catholic Church voter intimidation on issues like abortion and gay rights did not do so in spite of their religion, but rather because of it. Nationalism and patriotism were ably used by Lincoln, JFK and FDR to advance just, progressive, humanistic policies. All three, incidentally, also used patriotism and nationalism to advance decidedly unjust policies. In other words, these nebulous authorities are tools--the goals and character of those who wield them determine whether the cause is justice or hatred. The authority itself, so long as it exerts control over a heterogenous group, is not necessarily bigoted or beneficent in and of itself.
To put it another way, the American flag has represented many great and many evil things--the greatness and evil were never present in the actual cloth, but rather in the leaders whose actions it came to represent.
3. Those who use a major religion to promote bigotry must emphasize some aspects of its teachings and subvert othersTo make one example, you cannot follow the teachings of Christ and vote to deny any human being her rights, much less actively judge that human being. So how does this bigotry happen under religion's banner? Because religious leaders have rarely been directly concerned with the actual Scripture or holy laws: they elevate those parts useful for achieving their ends, and happily ignore any that would stand against them. John Stuart Mill nailed this total paradox very well:
Yet it is scarcely too much to say that not one Christian in a thousand guides or tests his individual conduct by reference to those laws. The standard to which he does refer it, is the custom of his nation, his class, or his religious profession.
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All Christians believe that the blessed are the poor and humble, and those who are illused by the world; that it is easier for a camel to pass through the eye of a needle than for a rich man to enter the kingdom of heaven; that they should judge not, lest they be judged; that they should swear not at all; that they should love their neighbor as themselves; that if one take their cloak, they should give him their coat also; that they should take no thought for the morrow; that if they would be perfect, they should sell all that they have and give it to the poor.
They are not insincere when they say that they believe these things. They do believe them, as people believe what they have always heard lauded and never discussed. But in the sense of that living belief which regulates conduct, they believe these doctrines just up to the point to which it is usual to act upon them. The doctrines in their integrity are serviceable to pelt adversaries with; and it is understood that they are to be put forward (when possible) as the reasons for whatever people do that they think laudable. But any one who reminded them that the maxims require an infinity of things which they never even think of doing would gain nothing but to be classed among those very unpopular characters who affect to be better than other people.
The doctrines have no hold on ordinary believers--are not a power in their minds. They have an habitual respect for the sound of them, but no feeling which spreads from the words to the things signified, and forces the mind to take them in, and make them conform to the formula. Whenever conduct is concerned, they look round for Mr. A and B to direct them how far to go in obeying Christ.
This is likewise shown in wholly secular debates, which are riddled with calls to secular authority. How many DUers have ironically quoted the lines written on the statue of liberty? "Give us your tired, your poor, your huddled masses longing to be free?" Where is that seen in the flag-draped anti-immigration movement? Again, it's not the edifice of authority that brings out the worst or best in us--it's those who make appeals to that authority in order to control large numbers of people.