Iggy nailed it.
I follow the market a little bit, and most analysts think that the stock run-up had a lot to do with increased investor confidence, due mainly to the investor-friendly rhetoric coming from the Trump administration.
The left really underestimates the drag regulations can impose on an economy. Under Obama, regulations had been ramping up steadily year after year, and in my opinion they have held back growth in the market, depressed confidence in the economy by investors and stunted small business startup rates.
So along comes Trump, who promises to roll back a lot of those regs. And, it’s not just talk - the people he has appointed to the various regulatory agencies are exactly the type who would roll back regs (if anyone can). Trump has also signed numerous executive orders undoing Obama’s executive orders.
That, plus his talk of tax cuts, the complete control of government by Republicans which should have in theory made it easy to do some of these things, and his plan for big infrastructure spending has juiced up those ‘animal spirits’ in the economy. I expect we’ll find that small business startups increase as well.
However… That talk has to be followed by action. There has actually been quite a bit of action on the regulatory front, but tax reform is looking iffy, the health care bill is turning into a debacle, and Trump’s idiocy may overshadow all of it if someone doesn’t immobilize his twitter finger.