Why conservative speakers are protested on college campuses

Simple answer: They keep touting arguments that have long been debunked. Take tax cuts for example: They keep insisting that tax cuts will pay for themselves despite the fact such a policy eventually cost' George H. W. Bush his second term when he had no choice but to raise taxes again.

Check these sources if you will:

NO, TAX CUTS ARE NOT PAYING FOR THEMSELVES

YES, TAX CUTS ARE PAYING FOR THEMSELVES

Committee for a Responsible Federal Budget: Do Tax Cuts Pay For Themselves?  The Fiscal Times: Are the Tax Cuts Paying for Themselves?  New York Times: No, Trump’s Tax Cut Isn’t Paying for Itself (at Least Not Yet)  FactCheck.org: CBO Didn’t Say Tax Cuts Were ‘Virtually Paid For’  The Washington Post: History lesson: Do big tax cuts pay for themselves?  Politifact: Do tax cuts pay for themselves? Evidence is thin / Trump economic chief Larry Kudlow wrong about CBO report on tax cuts

Investor's Business Daily: It's Official: Trump Tax Cuts Are Boosting Growth And Mostly Paying For Themselves.  The Wall Street Journal: The Corporate Tax Cut Is Paying for Itself  Forbes: The Tax Cuts Will Pay For Themselves If We Wait Long Enough YouTube: Mnuchin - Trump's tax cuts will pay for themselves. American Thinker: Trump's tax cuts already paying for themselves Town Hall: Dems Wrong Again: Republican Tax Cuts Are Paying for Themselves

Then there's Market Watch: Opinion: The unanswerable question: Do tax cuts pay for themselves?