The key word here is "overwhelming."

Well, I'm going to believe the CIA way more than I'm going to believe some guy on the internet. And if the CIA says it "believes" that a foreign state (a hostile one, too) tried to influence our elections, or even tried to hack our elections, that is something worth looking into.

I know that there is some disagreement within the intelligence community, FBI and CIA, but it's not like this was a thing back when McCain or Romney ran. This is pretty insane and should be taken seriously. McCain, by the way, is also calling for more information, so it's not just us butt-hurt, tinfoil hat liberals.

If for nothing else than to make sure it doesn't happen next time.

A user here collected all the evidence (lots of its, though circumstantial) that Trump has Russian ties.

At worst, Trump directly owes the Russian government lots of money (we don't know, he didn't release his taxes). At best, Russia didn't try to get him elected, but rather just wanted to fuck with our elections. The first would be very, very bad. The second is also very bad and Russia should probably be taken down a peg.