Yep. That is what comes across.
It's been there for a long time, especially in the GoP. It was a big part of what went so wrong in Iraq. And now it is unmodified and explicit in the domain of world trade.
Usually comes when an empire is about to fail. The English had it at the end of their empire. The Romans too. And it is fairly obvious that US authority is diminishing as its share of global GDP declines. A weaker power needs to use its elbows.
There's nothing special about any country. They are all populated with folks, none of whom are collectively better than those in other countries. A society gleans its advantages through stability, imagination, health, education and hard work over time, as well as available capital and resources. I don't see the US as having an obvious massive competitive advantage in any of these spheres any more.
A large, economically successful country exercises more power than a smaller one, of course. And it appears to me, at least, that this is most of the explanation of US residual power currently - as well as the fact that more populous places like India and China have been poorly administered. But they are catching up fast.
I don't see the US economy as relatively especially successful, although it has its strengths. In the aftermath of World War II, it had a massive advantage as most of its competitors had had their infrastructure destroyed. But many have caught up with the US in the ensuing seven decades. They have done so because they invested in common goods (such as education, healthcare and infrastructure) and because they developed their own capital markets.
The one area in which the US has invested more than anyone else is in its military. But in a few decades, China will surpass it.
So the "We're America, Bitch" comment really represents the loss of humility and complacency of a declining empire. Much of all that's left is the attitude.
The people who vote for Trump see themselves as victims of the world economy. Or put another way, they can't compete with the rest of the world and so they demand protections. Unfortunately, protectionism actually raises costs, so even if some farmers benefit, collectively US citizens will need to pay more for their goods. And then, of course, US exporters will have to face up to tariffs themselves in the global trade war which follows.
The rest of the world will respond not with conflict but navigation. If America acts selfishly, others will seek to avoid involving themselves with it. Being trustworthy and cooperative is, in fact, more efficient than selfishness. Just ask the game theorists.
G7 is dead. So there will be a G6. And I imagine the G6 will welcome countries like Australia and India into their meetings in time as part of a Commonwealth string of nations. One day, the US may ask if they might rejoin the world. And on that day, the world will doubtless open their arms and welcome it back to the family of nations. It needs to go through this stage first.