Capping four years of explosive growth sparked by the election of America’s first black president and anger over the economy, the number of conspiracy-minded antigovernment “Patriot” groups reached an all-time high of 1,360 in 2012, while the number of hard-core hate groups remained above 1,000. As President Obama enters his second term with an agenda of gun control and immigration reform, the rage on the right is likely to intensify.