Maybe what's different about combat in the past and todays "modern" combat isn't the weapons the soldiers carry, but rather the society the soldiers come from.
Soldiers who fought in WW1, WW2, and Korea were usually supportive of Americas cause for being there (fighting fascism, communism, whatever) whereas the troops in Vietnam and later didn't have the same sense of purpose. People were willing to die for their country back then, not any more.
The "CNN factor" must also be taken into account. Pictures of horribly mutilated american soldiers being broadcast live for the soccer moms to see causes a lot of problems for military leaders in trying to press a war to a succesful conclusion.
We stopped the Iraq war because we had defeated saddams army and the public didn't want to risk their son's in further combat because saddam might have used chem/bio if he knew we were intent on destroying him personally. Could you imagine the outcry from the soccer moms and liberals on seeing thousands of american troops dying in a meat grinder like a modern Iwo Jima or Flanders?
Remember how we pulled out of Somalia after CNN broadcast pictures of the dead american being dragged through the streets? Americans of the past era would be screaming for the heads of the enemy, utter annihilation of their cities, starving the populace into submission. Now we cry "Stop, pull out, retreat!". We can't stand the sight of american blood in battle despite all the blood we see every day on TV and in movies.
Face it, America has gotten weak. Used to be if someone messed with the US we'd invade and destroy them, execute their leaders, and restructure their entire society to fit our ideals. Now we talk of UN sanctions, "surgical strikes", embargos, and "no more most favored nation status". Puke.
And let's not forget the leaders of the country either. Is anyone seriously saying that Bill "I did not have sex with that woman" Clinton is an equal to FDR, Churchill, or even Stalin? Those men could lead a nation through years of total war. Clinton couldn't even get us through a bush skirmish (Haiti, Somalia, Bosnia) or sex scandal. Presidents (except Ron
) have gone ever faster downhill since Kennedy.