"A huge star in the Milky Way, Eta Carinae, has already erupted in a similar fashion. So if it explodes as a supernova, it could present the best light show seen, because it is a mere 7,500 light years away from our planet."

Eta Carinae is only 7,500 LY-

"peaking with a brightness comparable to 50 billion suns," means a whole lot of energy would still reach us, if Eta Carinae was to blow.

Not sure if it would be limited to visible light- X-rays and IR might have an effect, as well. But we will just reduce CO2 emmissions, blame the US, and it will be ok...