The so-called "Founding Fathers" were strongly opposed to professional armed forces for exactly that reason: it's less likely that ordinary citizens recruited via conscription would be sent to fight "bullshit wars".

Vietnam changed all that, or, more to the point, verified it. The anger against the war was fueled by the fact that anyone could be sent to fight it. Politicians realized that wars would not create such uproars if they were only fought by professional soldiers.

And indeed this is true to this day. Most Americans don't care about US foreign wars, because for them personally the stakes are low.