Liberals were once slavers. It doesn't really matter what they did, it matters what they do now. And right now they are quite literally on an anti-God agenda. How can one say it's not good to be conservative when they are the main ones upholding Him?
Actually, it wasn't the liberals who were the slavers. It was Democrats who were slavers but, don't forget, in the early part of the 20th century, thanks to progressive propaganda, "liberal" came to mean precisely the opposite of what it did before. "Liberal" has its root word in
liberty, because, traditionally, liberals defended freedom and liberty, things such as small government with little power to regulate people, and de-centralized government, so that power was closer to the local level so that government was more accountable.
This is why there is a branch of Libertarianism called "Classical Liberalism", because they are the ones who believe in the traditional tenets of liberalism. Ironically, by the original definition of liberalism, I'm far more liberal than any modern liberal here.
Around the time of Woodrow Wilson's administration, Progressives felt that people were starting to catch on to what they were, which was pretty evil. So they co-opted the name "liberal", even though they were anything but, to try to convince people, "Hey, I'm just like you".
The name persists to this day. That's why, even though "liberal" has the word liberty built into it, they stand for anything but. Rather than liberty, modern liberals stand for the regulation of every part of our lives.
Hope this helps.