I'm a Catholic and a Democrat, mostly in that order.When Jack Kennedy ran for president, the two overlapped as much as "Mormon and Republican" seem to today.Now, even though Vice President Joe Biden and House Minority Leader Nancy Pelosi, D-Calif., are Catholic Democrats (and Senate Majority Leader Harry Reid, D-Nev., is a Mormon Democrat), it's increasingly uncomfortable to be both. Angry voices in my church and in my party are squaring off against each other in an increasingly noisy and ugly confrontation.I tend to take the long view. That comes in handy in a church that's been around more than 2,000 years and a party that's been around nearly 200 years. The history of my church has its share of dark moments, from immoral popes to inquisitions. And for decades, my party was on the wrong side of battles for racial equality, and not just in the South.Right now, unfortunately, those who forget history on both the right and the left are using raw political muscle to demonize dissent, with the mirror-image goals of driving Democrats out of the Roman Catholic Church and Catholics out of the Democratic Party.Conservative Catholics and the church hierarchy are pressuring lay Catholics to turn a debate over healthcare policy, specifically contraception coverage, into a litmus test of religious freedom. Supporters of women's rights and marriage equality are increasingly insisting that their allies turn their back on their church.Turning principled disagreements into partisan "wedge" issues is a cynical ploy that all Americans have a stake in thwarting.If matters of faith and conscience can be exploited to manipulate the outcome of national elections, we go backward as a nation. And if matters of economics and social policies can be exploited to manipulate our choice of houses of worship, we go backward as a people.It's not simply that we've avoided the bloody sectarian conflicts of other nations by building a separation between church and state. We've also maintained a healthy balance in which faith and politics can interact to call us to our better selves.The civil rights struggle would have been far more violent and poisonous if the Rev. Martin Luther King Jr. had not explicitly appealed to the shared Judeo-Christian heritage of most Americans at the time. Cesar Chavez would have been crushed in his crusade for human dignity for immigrant workers without the aid of his Catholic faith and allies.Our history is uplifted by countless men and women of faith who have brought their transcendent values to both public debate and courageous social action.It's vital that we continue to maintain that balance, not a rigid segregation of faith and politics but a healthy tolerance of varied voices in a diverse nation.Most Americans would be comfortable with the admonition in the Book of Micah that what God truly requires of man is "to act justly, to love mercy and to walk humbly with your God."In America, we've overcome dark chapters of intolerance to build a nation where we are free to choose our own faith and our own party, or to choose not to align with a faith or a party. That's become a resilient foundation for mutual respect. Let's resist efforts to curb that freedom and diminish that mutual respect.Rick Cole is the city manager of Ventura, Calif. He wrote this for the Los Angeles Times.