It is not their belief, or lack of belief, in God. Many conservatives are atheists, and many liberals are theists. Nancy Pelosi is a professing Roman Catholic, but atheist George Will, noted columnist, is a well-respected conservative.
The difference between a political conservative and a political liberal is not their belief about God. It is their conviction about human nature, what theologians call our anthropology. Are people basically good, or basically selfish, acquisitive, and narcissistic? That is the question. In his book, A Conflict in Vision, economist Thomas Sowell, not a Christian, argues this point persuasively. So does a recent YouTube video by Prager University.
Here is the great irony. The more confidence we have in the goodness of human nature the more evil we will become. The opposite is also true. The less confidence we have in human nature, the more virtuous we will generally become. Think about these examples.
Your belief on human nature will govern your approach to child rearing. If you think children are inherently selfish and self-centered, you will discipline them. If not, you will despise corporeal punishment. Your parenting style will be permissive. Your children will mature with their narcissism in full flower. The evidence of their sinful nature is overwhelming. Children don't need to be taught to be evil. They are naturally evil. They need to be taught virtue, and if they are not taught virtue, they won't be virtuous.
Your belief about human nature will determine your approach to personal responsibility. Are people fundamentally responsible for the choices they make in life? If the heart is fundamentally self-centered, then I am responsible for the bad choices I make. But, if I am fundamentally good my problems and successes cannot be the result of my heart disposition. My environment, something outside of me, i.e. parenting, education, social status, neighborhood, etc., must be the problem. The latter view is called "Environmentalism." I am not responsible. My environment is.
If our environment is the problem then government intervention is the solution. Billions will be spent on anti-poverty programs, education, etc.
But, if you believe that people are basically self-centered and selfish, then no amount of environmental change will help. A change of heart is the only solution, and hearts only change through strong families, religion, and parenting. This is why conservatives generally push for strong families and limited government.
Police and Military
Your belief about human nature will shape your convictions about the role of military and law enforcement. If people are basically good, we need limited law enforcement. If people are basically good we don't need to fear China or Iran. Their attitude towards us will surely be benevolent. We can trust them to keep their agreements. We do not need a strong military.
But, if people are basically covetous, dishonest, and selfish, we need a strong military. Our foes cannot be trusted. We know from history that the best way to preserve peace is to convince our potential foes that an attack on the U.S. will be their undoing. That is why "Peace through Strength" is the conservative motto.
Your belief about human nature will determine your economic theory. Capitalism is the economic system for sinners. It harnesses the human lust for material gain and makes it serve the common good. Because people are basically lazy and dishonest, the capitalist realizes that it cannot help those who will not try to help themselves. Even Jesus said, the poor you will always have with you.
Socialism is the economic system for idealists. Believing that people are basically good, the liberal believes it can pass out government checks and people will not abuse the system. Believing that people are basically good ,the liberal believes government can penalize the productive with onerous taxes and they will still produce.
Because of their belief in the goodness of human nature, liberals tend to be Utopian. They believe that, if we just try hard enough, we can create the perfect society. Communism was Utopian. The last century alone should convince us that utopianism is a terrible error. With this view of human nature Stalin slaughtered somewhere in the neighborhood of 20 million Russians. "You need to break a few eggs to make an omlette" was his famous rationalization.
Similarly Mao Zedong, attempting to create a social utopia in China, butchered somewhere between 60 and 80 million Chinese.
Isn't it amazing that these men could be so patently evil themselves, and still believe that people are basically good? "The heart is deceitful above all things. Who can understand it?" Our capacity for self-deception is astounding.
The Bible is realistic . It does not flatter us. This is why most conservatives are Believers. "And the Lord saw that the wickedness of man was great in the earth, and that every intention of the thoughts of his heart was only evil continually" (Gen 6:5). "All have turned aside; together they have become worthless; no one does good, not even one" (Romans 3:12). The less confidence we have in human nature the more virtuous we will become. The ultimate change of heart that brings true virtue is conversion to Christ. For our good and the good of our children, let us humble ourselves, and confess our sins, so that we can grow in moral goodness.