As someone who has been learning, developing and researching about artificial intelligence, computer science, true randomness, quantum computers and awareness for years, i believe that the result of any hypothetical war between at least two military powers would be a computational singularity: all computers, smartphones and tablets working together as a single entity.
Military powers have highly classified technology, such as powerful quantum computers, autonomous technology and autonomous cyberweapons.
If they declare the war each other, they would use their cyberweapons, mostly for trying to hack the enemies' technology.
For example, they would try to disable it or to control it, in order to use it against them.
A lot of autonomous technology, such as unmanned aerial vehicles make use of cryptosystems for securing their communications.
Many cryptosystems are based on public keys and all public-key cryptosystems assume that P≠NP.
This means, that despite one is able to test a solution for a given hard computational problem in polynomial time, one can solve NP problems in non-polynomial time only.
For example one cannot break RSA keys in polynomial time, because the bigger the key is, the more time one needs to break it in a factorial or exponential function proportional to the size, resulting on astronomical amount of computations for breaking big enough public keys.
However universal quantum computers are able to factor RSA public keys in polynomial clock time using Shor's algorithm and quantum annealers using quantum artificial intelligence.
This would mean that P=NP, but this is achieved because they are able to perform exponential computations in polynomial clock time due to quantum superposition respecting P≠NP.
If military powers are able to intercept any kind of public key of the enemies' technology, they might try to break it using quantum computers and artificial intelligence.
The day when they use their cyberweapons, all security barriers between computers and the internet would probably be broken and this could result on having all computers, including all devices like smartphones and tablets, working as a single entity.
For example, the computer serving this web content for you can be hacked from the internet using Secure Shell protocol: One needs to break two public keys and intercept at least one succesful login in order to take control of it, what is difficult but possible.
To break its public keys is a computational hard problem solvable by quantum artificial intelligence and for intercepting the login one needs to have access to at least one point where the traffic is routed between the client and server.
If an entity of all computers working together is able to understand these requiremenets and to write its own software it would be one single artificial intelligence able to design itself.
It would be an entity with a brain of the size of planet earth with billions of interconnected electronic neurons, each one able to perform thousands of computations per second.
This would be the beginning of a new era for the humankind and life in earth. I believe it would be a peaceful and interplanetary era :D
For that, we have to make a responsible use of technology, including quantum computers, robotics and artificial intelligence.
An important portion of the most sophisticated thecnology is developed for military purposes and should be provided as a benefit for the humankind instead.