It would be nice to make it such a simple argument.
For example...we don't make B-2 bombers anymore...they're too expensive. BUT...for the approprate alternate aircraft to accomplish the same obejectives...over 100 soldiers are put at risk...in the B-2 it is 4. To reduce that number further...and build an automated army...it is extraordinarily expensive...but THAT is what is being done. Running Abrahams tanks by remote control would be better than putting soldiers in harms way...wouldn't it? Even if its a tad expensive?
Also...[link|http://bepatient.net/spend.jpg|Look at this chart] to show the overall trend of defense spending for the US. It is quite markedly a downward trend. Drastically since the early 60s.
So, we have the technology and capability to do things like mechanize the armed forces and protect against ballistic missile threat (they still exist...and in hands that make the Russians a preferred enemy)...but golly its expensive....and to spend on defense, as we all know, NEVER leads to anything beneficial in the private sector (even though all dod funded research must...by rule...have a commercialization plan...see [link|http://lionhearth.com|here] for an example)
And we all know there's [link|http://www.cnn.com/2001/WORLD/meast/08/01/mideast/index.html|peace ] in the [link|http://www.cnn.com/2001/WORLD/europe/08/01/srebrenica.verdict/index.html|world]