I haven't seen US economy this versatile and powerful in a long time, maybe since the 80s. This economy is diversified - manufacturing jobs used to be 32% in the 60s, now it is around 9% currently, but it is growing fast this year. We now have new jobs in every sectors growing, from finance (NY), college (Boston), healthcare (east coast), government (Washington DC), entertainment (Los Angeles), oil and gas (Texas), import/export (Cali/Florida), tourism (Florida), agriculture (flyover), and of course, tech (Silicon Valley, Seattle). And each industry is evenly distributed and growing. Thus the low unemployment rate and wage increases (higher in industries with higher demands)
US has gone through lots of challenges (globalization, gas/oil crisis, 9/11, cold war) in the last 50 years, and has come out on top every time.
4% growth is huge for the largest economy in the world, and the economy is nearly double the size of the closest competitor country. Bay Area alone is nearly a trillion dollar economy, and has double the growth rate of any other county in US.
Coupled with the flooding of capital back to US via the reduced expatriation tax rate, US is firing on all cylinders.