First of all, the Liberals are the dominant group politically in the US and other Western nations. Therefore what Liberals want they usually get; no surprise to anyone with a knowledge of human events.

Second, the opposition to Liberals, classified as conservative by Prothero, is made of of disparate and often opposing groups, many favor/don't oppose the great Liberal victories of which Prothero boosts: legal pot and legal sodomy. Destroying freedom to own guns, an issue that all non-Liberals oppose, has not gone gone too well for the Liberals, as even the professor concedes. Internet freedom is still with us, in spite of massive Liberal opposition.

Also, while JFK might be classified as Liberal, in no way could Thomas Jefferson be considered Liberal. Jefferson flourished in the 18th century, today's political categories are not relevant.