Because of stuff like this:
"The Senate voted Wednesday to permit passengers on the Amtrak passenger railroad to transport handguns in their checked baggage. . . . "Americans should not have their Second Amendment rights restricted for any reason, particularly if they choose to travel on America's federally subsidized rail line," said Sen. Roger Wicker, R-Miss., who made the proposal. Wicker's amendment would deny the railroad its $1.6 billion taxpayer subsidy unless it changes the gun policy."
Why do people need guns in their baggage on passenger trains?