If 90% of the hash is forced to go offline (which could easily happen is such a war scenario) we'll have more than a "little bit of delay." Blocks won't be mined for months as difficulty adjustment has a maximum adjustment allowed every 2 weeks. Just something to think about 

needcreations_

Not sure what will happen to your "crypto" but all btc will still be safe onchain.

The miners will find a way to mine with a litte bit of delay an some reorgs, and i am sure that you will find a way to broadcast a tx. If not you have to wait till internet is back.

You can lose your life in ww3 or the private key, but it is literally impossible to lose bitcoins.

AccessTribe

If world war 3 begin and there is no internet,what will happen to our crypto? 

Not sure what will happen to your "crypto" but all btc will still be safe onchain.
The miners will find a way to mine with a litte bit of delay an some reorgs, and i am sure that you will find a way to broadcast a tx. If not you have to wait till internet is back.
You can lose your life in ww3 or the private key, but it is literally impossible to lose bitcoins.