Many political issues end up being framed as “pro vs “anti”. Pro/anti immigration. Pro/anti drugs. Pro/anti choice. Pro/anti life.
But a pro/anti framing is almost always subtly dishonest. When you say you are pro-life, do you really believe people who disagree with you are against life!? When you say you are pro-choice, do you really believe people against you are against choice!?
Obviously not. You are pro/anti legalized abortion. But by calling yourself pro-life or pro-choice, you imply that the other side is anti-life or anti-choice, which sounds bad. It is a subtle, but effective, way of manipulating people’s opinions.