“Should we be seen as a hegemon that imposes its will on others, or as a beacon"?

Here is an enlightening article from the New Statesman. In it, the author is invited to hear the result of a lengthy study by a group of up-and-coming officers at the National Defense University at Fort McNair. This group was faced with a difficult burden: “In short, what should America do over the next decade to sustain its global pre-­eminence?”

Their finding was that the chance for the US to shape global politics will have passed significantly by 2021. Other findings were even more startling:

It should not to go to war with Iran. “We have to be able to learn to live with a ­nuclear-armed Iran,” the briefer said. “The alternative [war] would impose far too high a cost on America.” In Asia, the US should recognise the inevitable and offer the green light to China’s military domination of the Taiwan Straits. In exchange for the US agreeing to stand down over Taiwan, China would push North Korea to unite with South Korea. Finally, the US should stop spending so much time and resources on the war against al-Qaeda (the exercise took place about three weeks before Osama Bin Laden was killed). All this was a means to an end, which was to restore the US’s economic vitality.

They went on to say savings from military draw-downs should be spent on infrastructure, education and foreign aid. Was this possible? The presenter said:

“We would need to persuade our friends on the Republican side that America has to share power if we want to free up resources to invest at home,” the briefer said. “We tried really hard to come up with alternatives. But we couldn’t find a better way to do this.”

The writer was also able to interview Admiral Mullen’s, Chairman of the Joint Chiefs of Staff at the time. He is quoted in the article as saying:

“We are borrowing money from China to build weapons to face down China,” he said. “I mean, that’s a broken strategy. It may be OK now for a while, but it is a failed strategy from a national security perspective.”

The writer then made the point drawing from Adm. Mullen’s words:

Mullen spoke of the need for Washington to take more effective decisions at a time when the US is entering a lengthy phase of fiscal austerity. It was clear he did not think Washington was up to the task.

I encourage all interested parties to please read the article.

My questions are:

Is American hegemony important?
If American hegemony is waning, what sort of world should we strive for?
In a world where force is more balanced between various powers, what should an American role be?
As an individual American, what can we do to bring about change?