A country wide outage is highly unlikely. As long as there are suitable methods of transportation, you'll always be able to get to a location that will at the very least allow you to access the internet via mobile, which will in turn allow you access to your coins
You won't be able to access internet at all when your city gets hit by a tornadoes and all the phone lines are downI love Bitcoin and love the anonymity it provides, but we can't completely stay away from fiat money yet, we still need those for a lot of stuffs
Unless, we have a physical Bitcoin that accepted at stores
Fiber optics are buried deep beneath the ground, so there is a chance that internet connection is available for those people who availed fiber connections. As for physical bitcoins, I don't think it would be that viable since you need to print or create something like fiat, plus transactions won't be recorded on the blockchain too.
Some still use an old phone lines to access the internet
I was joking about the physical Bitcoins
That idea sounds ridiculous and wouldn't happen in a long run