Yes you can have your Bitcoin In time of wars if you stored it in the right way....
Which means you can still lose it if you hold your coin in an exchange wallet and the exchange company gets affected on war... there might be a compensation maybe after the but that's on a very low scale.
Using a non custodial wallet to hold your coin cab still give the safety for your coin in time of war, just keep you seed phrases safe and you will be fine to withdraw your coins so far there are still active miners to mine themand include it in their various blocks .
During times of war, the banks and many business/financial sectors get really affected even when the war is over, cause it would take the banking system a while to start functioning properply again especially if the building got heavily affected, so Bitcoin is the best alternative people could use to carry out transactions and it would work perfectly since it's blockchain enables a safer and faster transactions.
Yeah, storing in a non-custodial wallet is right. Well apart from war related issues, i think those that are storing their assets for a long-term purpose, shouldn't think of storing them in an exchange but a non-custodial wallet like Electrum, Atomic wallet or even coinomi those are the safest place I could recommend anyone to store their Bitcoin, which can also be very efficient during times of war.
However people should protect their seed phrase at all cost, I think the best place to safe it in a situation of war is in a mail that's secured with a two factor authenticator cause if you write it down somewhere and keep in a safe or vault your home could be affected by war and the safe destroyed or buried to the ground but you could easily log into your mail after the war and have your seed phrase.