For me the change would be simple:
that we the people realise we don't have what the myths say we have and demand that we get it

We should demand Freedom. Real freedom. Freedom of religion. Freedom of speech. Freedom (as FDR said) from want and freedom from fear. Freedom to be individuals not conformists that are easy to rule over and to sell to, melting together into a uniform blob. Even freedom to own weapons, not to protect ourselves from our government or from each other (sure signs that the society isn't mature enough for guns), but for recreation, to sustain and explore traditional lifestyles and perhaps even simply because it used to be the domain of the elite only.

We should demand opportunity. We should demand the American Dream: that anyone willing to work hard should be able to do what they love, live comfortably and without fear of losing everything in the next Capitalist bubble. We should demand an end to the entitlements of the wealthy, feeling they have a right to power, wealth, security, opportunity not from hard work but by virtue of their wealth. We should demand an end to the race to the bottom where states compete with each other and other nations to see whose people are willing to give more to enrich the rich. The wealthy too should demand to be allowed back into the human race, not compelled to behave inhumanely in exchange for security that is anything but secure.

We should demand to be exceptional. We should demand a genuinely new and innovative form of government that isn't just more of the same going back to the beginnings of civilisation. We should demand government of, for and by the people. We should demand that nationalism and patriotism not be used as tools of oppression but an expression of identity only for those that choose to associate with the national traditions and the identity they imply. We should demand that our government not put our security at risk in service of the elite and then use insecurity to deny us freedoms.

We the people should return to how we were in the early 18th century, only more confident that we can be a great society. At the beginning of the 1700s places like Boston and Philadelphia competed with Europe not in terms of the greatest mansions and palaces for the wealthy, but in how they made sure the greatest number of people had opportunity to pursue their dreams with clean cities, strong public infrastructure, plentiful opportunity and a strong safety net. The people of the founding generation (not the fathers, the people themselves) knew that the government introduced by Hamilton and Madison was of, for and by the elite. In those days it was the landed elite of the south and the merchant elite of the north, but elitist as much as the aristocrats of Europe and almost as much so as the capitalist elite of today. It's why they refused to fight in the war. The army had to rely on new immigrants, freed slaves and convicts to fight, and of course the might and resources of the French. Hamilton admitted clearly in the Federalist Papers that the government would be of the elite, but that they could be trusted to act benevolently. The people knew better. The government was designed to prevent the people from challenging the power of the elite, it was worked wonderfully. When the opportunity came up the people headed west (to places like Tennessee) where they opened up the political system briefly to the people (expanding the right to vote beyond the tiny percentage that could vote early on). Then as the elite moved west the people moved further west, leading to the Progressive Era that pushed back the blatant and open rule by the elite of the robber baron era. It was a time when the people again made headway until the elite leveraged the Great War to shut the people down. In each case the elite quickly responded and closed down any real government of, for and by the people, a myth that wasn't introduced until Lincoln, a bit of revisionist history nearly 100 years after the founding of the country (nearly a hundred years of bonded slavery mixed with wage slavery).

We were the land of opportunity first because of the land we took from the original inhabitants and second because the manufacturers in the east needed to attract Europeans to the continent to lower the cost of labour (forcing more people into desperate poverty). So we became the "Land of Opportunity" (TM) as part of a marketing stunt to trick people into working hard to enrich the rich. Canada was the land of the free, where people wished to escaped to in order to get away from the enslavement of the United States.

We the people have power now but we've fallen for the myths and so are still controlled. If we realised that we don't have what we've been told we have and demand that we get it (and work together to develop it) we can change the world. The elite in their over-confidence have given us that power, knowing we won't use it. But the elite are us too, lost to the manic logic of our economic system.

We would, of course, have to invent a new form of government, invent a new form of economy and rediscover our humanity, but it would only mean being who we say we are. That is all it takes. And then, I think, everything else listed in the other answers takes care of itself, just as a matter of course.

I am not sure what the confines of "culture" are so if I've strayed too far, I apologise.