It does not reduce the worlds population in a significant manner...

It does not reduce the worlds population in a significant manner as to reduce it permanently. India breeds the Australian population every two years or so

12,819,359 Indian population growth rate per year.

Not to mention China now has a two child policy so there population growth rate will skyrocket now.

War in the ME does not keep Australia or the US any safer and in fact you now have thousands of jihadists in the US that werent Jihadists before the Gulf War. ME immigrants typically have a much higher birth rate than the average US or Australian family.

As for 500,000 killed I would say that does not take in the first Gulf war. Their were 100,000 soldiers killed in their trenches let alone the rest of the civilian population.