As always, when a war stretches on for a long time with no end in sight and with few of it's goals accomplished, the people start to lose their will to wage war. That is unless they are threatened (or are made to believe they are threatened with propaganda) by total annhialation.
The loss of support for the War on Terror is simply because the wars have dragged on for so long, and in the case of Afghanistahn, has yet to accomplish many of it's goals and has stretched on for nine years and has cost more than a trillion dollars and thousands of lives. Todays people are far too squeamish for my liking, we lost hundreds of thousands in the world wars against foes who had no realistic chance to destroy America (though it is entirely possible the central powers might have won if we hadn't stepped in, the Axis powers would have lost to the British Empire sooner or later, neither could do much more than sink trade ships or harass coastal cities.)
Sure, now days, War is extrodinarily expensive, (if we tried to mobilize as many troops, ships, vehicles, guns, aircraft and men as we did in WW2, our economy would most likely collapse under the strain), but the cost of life is nowhere near as high on average as it once was.
On the topic, I have little faith in stealth technology, low pulse radar has already proven itself as capable of defeating the F-117 nighthawk, and with that secret out, it is only a matter of time before our current stealth technology is completely worthless.
