OR, the Dems could nominate the right candidate next year and Trump will be removed from office. It's even possible Mitch McConnell will be removed from office next year, since his approval rating in Kentucky today is at 34%. His opponent is running as a conservative Democrat, which is what she has to do in Kentucky to win.
I don't see any group getting 38 states to sign on to rewrite the Constitution right now. If it happens, there will be states that will definitely secede from the US. Do you really think California will tolerate a government with a racist, right wing Constitution? California is the 4th largest economy in the world, BTW. I would predict citizens from the states under the new kind of government would migrate to any of the states that had left the US . I would also predict that the states that stayed in the US wouldn't be able to sustain themselves absent the tax base and manufacturing capabilities of the states that left. They would fall into economic collapse.
I'm really not worried about it though, because the Dems are going to do the right thing in 2020 and get their man or woman elected. The Roaches will crawl back into their holes and hide again. Just a little more than a year and a half now, and time passes very quickly.