Here are a few bracing excerpts from a talk Archbishop Charles Chaput delivered in Toronto back in 2009. The whole presentation is worth a read.

The “separation of Church and state” does not mean – and it can never mean – separating our Catholic faith from our public witness, our political choices and our political actions. That kind of separation would require Christians to deny who we are; to repudiate Jesus when he commands us to be “leaven in the world” and to “make disciples of all nations.” That kind of radical separation steals the moral content of a society. It’s the equivalent of telling a married man that he can’t act married in public. Of course, he can certainly do that, but he won’t stay married for long.
Partly because I’m a bishop and partly because I’m older and a little bit wiser, I don’t belong to any political party. As a young priest I worked on Bobby Kennedy’s campaign. Later I volunteered with the 1976 and 1980 campaigns for Jimmy Carter. So if I have any partisan roots, they’re in the Democratic Party. But as I say in the book, one of the lessons we need to learn from the last 50 years is that a “preferred” Catholic political party usually doesn’t exist. The sooner Catholics feel at home in any political party, the sooner that party takes them for granted and then ignores their concerns. Party loyalty for the sake of habit, or family tradition, or ethnic or class interest is a form of tribalism. It’s a lethal kind of moral laziness. Issues matter. Character matters. Acting on principle matters. But party loyalty for the sake of party loyalty is a dead end….
One of the words we heard endlessly in the last U.S. election was “hope.” I think “hope” is the only word in the English language more badly misused than “love.” It’s our go-to anxiety word — as in, “I sure hope I don’t say anything stupid tonight.” But for Christians, hope is a virtue, not an emotional crutch or a political slogan. Virtus, the Latin root of virtue, means strength or courage. Real hope is unsentimental. It has nothing to do with the cheesy optimism of election campaigns. Hope assumes and demands a spine in believers. And that’s why – at least for a Christian — hope sustains us when the real answer to the problems or hard choices in life is “no, we can’t,” instead of “yes, we can”….
[Georges] Bernanos once wrote that the optimism of the modern world, including its “politics of hope,” is like whistling past a graveyard. It’s a cheap substitute for real hope and “a sly form of selfishness, a method of isolating [ourselves] from the unhappiness of others” by thinking progressive thoughts. Real hope “must be won. [We] can only attain hope through truth, at the cost of great effort and long patience . . . Hope is a virtue, virtus, strength; an heroic determination of the soul. [And] the highest form of hope is despair overcome.”
Anyone who hasn’t noticed the despair in the world should probably go back to sleep. The word “hope” on a campaign poster may give us a little thrill of righteousness, but the world will still be a wreck when the drug wears off. We can only attain hope through truth. And what that means is this: From the moment Jesus said, “I am the way, the truth and the life,” the most important political statement anyone can make is “Jesus Christ is Lord.”