I'm having a little trouble understanding why one can't be both a social conservative and a small government Republican.
Because social conservatives want "Big Government" to prevent abortion and "mercy killing."
You had that for much of the country's history when there was a social consensus. Among other gifts the 60s left us with a culture war. Progressives using the Supreme Court to force their mores on the whole country spawned attempts by both sides to use the government to their own ends.