Christian apologist Frank Turek writes about it at Townhall.
Excerpt:
When I hear Christians saying we ought not get involved in politics but just “preach the Gospel,” I show them this satellite picture of the Korean peninsula. Here we see a homogenous population of mostly Koreans separated by a well-fortified border. South Korea is full of freedom, food and productivity—it’s one of the most Christianized countries in the world. North Korea is a concentration camp. They have no freedom, no food, and very little Christianity.
What’s the primary reason for the stark difference between these two countries? Politics. The South politically allows freedom, while the North does not.
Ironically, Christians who shun politics to supposedly advance the Gospel are actually allowing others to stop the Gospel. How so? Because politics and law affects one’s ability to preach the Gospel! If you think otherwise, visit some of the countries I have visited—Iran, Saudi Arabia and China. You cannot legally “preach the Gospel” in those countries—or practice other aspects of your religion freely—because politically they’ve ruled it out as they have in North Korea.
In fact, politics affects virtually every area of your life through the laws made by government. So if you care about your family, business, church, school, children, money, property, home, security, healthcare, safety, freedom, and your ability to “preach the Gospel,” then you should care about politics.
Politics affects everything, which is why leaders throughout the Bible—including Joseph, Moses, Daniel, Nehemiah, Mordecai, Esther, John the Baptist, and Paul— “went political” to influence civil governments to govern morally. Even Jesus himself got involved in politics when he publically chastised the Pharisees—the religious and political leaders of Israel—for neglecting “the more important matters of the law.”
[…]But what can Christians do? After all, we can’t legislate morality, can we? News flash: All laws legislate morality! Morality is about right and wrong and all laws declare one behavior right and the opposite behavior wrong. So the question is not whether we can legislate morality, but “Whose morality will we legislate?”
[…]When we fail to legislate morally, others impose immorality. For example, totalitarian political correctness is already imposed in states such as Massachusetts where the implications of same-sex marriage override the religious liberties of businesses, charities and even parents. As documented here and illustrated here, same sex marriage prevents you from running your business, educating your children, or practicing your religion in accord with your Conscience. And soon, as is the case in Canada, you may not be able to merely speak Biblically about homosexual behavior. That is because those who say they are fighting for “tolerance” are often the most intolerant.
Unless Christians begin to influence politics and the culture more significantly, we will continue to lose the very freedoms that enable us to live according to our beliefs and spread the Gospel all over the world. That’s why you should not vote for candidates because of their race or religion, but because they will govern morally on the more important matters of the law—life, marriage and religious freedom.
Dr. Turek says that some societies make it easier for us to carry out our responsibilities as Christians, such as evangelism. That’s true. But I want to make a different point from Dr. Turek related to the point that he made.
I get a lot of e-mails from people complaining that I spend too much time on fiscal issues, and especially on foreign policy. But I really think that Christians need to branch out and read widely about these issues, too. The more we know about everything, the better we will be able to connect what the Bible says to every area, and the smarter we will be at laying out plans for our lives and achieving the good goals we set for ourselves as part of our relationship with God.
It’s always better to know how things work. What good is it to say that you want to achieve some aim like helping the poor or making the world more peaceful unless you first study economics and foreign policy so that you will know how to achieve it? Many people try to achieve these goals by embracing policies that sound good, but they actually achieve the exact opposite ends that you set out to achieve. If you want to drive a car to get somewhere, you must first learn how to drive a car. Why should faith be any different than anything else? Don’t take positions based on feelings or peer pressure, get informed and make a right judgment.
WINTERY KNIGHT 
