Democrats have tried to make the “Koch Brothers” public enemy no. 1 for their support of conservative candidates and causes. Last year, then-Senate Majority Leader Harry Reid, D-Nev., even labeled them “un-American.” But in an interview with “Morning Joe” co-hosts Mika Brzezinski and Joe Scarborough, Charles Koch says he’s not intimidated. “It’s frightening for the future of the country to have these public officials try to hurt and destroy private citizens who oppose what they’re doing.”