Yes, war will become more deadly in the future, because we have more weapons available to us. With the invention of airplanes, terrorists were able to kill thousands on September 11. They may have killed more in the flight disappearance in Vietnam this weekend. Better weapons allow for more killings.
I think that ware will become more deadly in the future. I think that with the advancements of technology and science, it is only a matter of time till war becomes even more deadlier than the wars of today. I think that it is also only logical to think that wars will become more deadly.
In the future, it can be argued that war will be much more deadly than it is now, and especially more deadly than it was during World War II. With the creation of more powerful nuclear weapons and other nuclear warfare, future battles will be extremely deadly. They will also be dangerous to the Earth itself. A nuclear war would destroy the Earth.
I believe war will always be deadly and I think we will see major changes in the way wars are fought, but I do not believe that will make them less deadly. I think cyber warfare, if done correctly, could easily turn to death in a society. Causing chaos can be deadly without firing a single bomb or weapon.