That depends on the war.

If the war threatens the integrity of the Internet then the value of cryptocurrencies will plummet. Think of North Korea threatening the US with an EMP device or the Russians cutting the undersea cables - they have been snooping around them with their submarines. In that case you'd be way better off with gold.

If the war just gets expensive and threatens the financial system then the value of cryptocurrencies should rise. You'd be ok with gold then too.