The answer is NO! While there is still war as something possible in a socialist world, it is likely to be less frequent. With capitalism, there will always be war as a constant thing, because the system profits from the industry, which depends on governments to buy its products. Socialist countries would be less likely to buy the industry's products, and would instead spend their money on providing for the basic needs of its people.

An excellent question, one that cuts to the very core, the very fiber of our present day existence.