I think there are two things that are obvious. First, Donald Trump will not win the presidency of the United States of America. And second, Trump is not a Republican. So the question is - what do the Republicans do after Trump?
I think they need to learn two things. First, that the Republican voters (all voters, actually) no longer believe in Conservative Dogma. And second, that the primary system that produced such an abomination at the head of their party needs a radical overhaul.
Regarding dogma. Trump doesn't actually have an ideology. I think all he did is listen to talk radio, Fox News, and hideous alt right media like Breitbart and Infowars to find out what were the hot issues that would attract votes from those who were locked into those "news" sources. I don't think he either cared about or knew how extreme some of those sources were, and how extreme some of those followers were. He got the fringe, and it is a shock to me that the "fringe" was so widespread amongst Republican Primary voters. Probably surprised him as well. I don't think he ever wanted to be president, I think he just wanted attention and a burnishing of his Brand, and a way to increase his revenue by getting a really good contract for his TV shows.
When Trump talks to crowds he becomes mesmerized by their reactions to him, and their reactions escalate the more extreme he becomes, so it becomes a sickening downward spiral into the darkest corners of the body politic - racism, hatred, revenge, violence, threats, any and all toxins that enters his brain in the moment that will generate what he really needs most desperately - attention and worship.
So, what can the Republican Party learn from Trump's triumph in the primaries? That very few conservatives care at all about ossified Conservative Dogmas. There were very qualified and articulate candidates representing the old hit tunes in the Republican jukebox - evangelical social conservative greatest hits, libertarian shrink the government golden oldies, send-our-children-to-war-military-aggression-to-show-what-majestic-leaders-we-are Great American Standards. The voters didn't care.
The old dogmas of the Right are obsolete. They don't address actual problems of today's realities. The forgotten aging white middle and lower middle classes know that the old conservative horses are worn out and ready to be put out to pasture. The idea of lowering taxes, shrinking the government, pushing fundamentalist Christian social obsessions, and scaring the crap out of the world does nothing for them or the country. They have stopped buying the dogmas that made sense during Reagan's time, but have run their course and need to be put out to pasture today.
So, what I expect the Republican Party to do is to ignore this message and decide that the problem was that Trump wasn't a true Republican, and the Evangelicals and the Shrink-the-Governmentalists, and the Lower the Taxes on the "Makers" and lower the assistance to the "Takers" folks will all fight like crazy to take on the mantle of True Conservatism and they think they will sweep the "Conservative Movement" into its rightful place in charge of the country and the world.
But they will fail because each of those ideologies has failed, and the Republican voters have already said that loud and clear when they voted for Trump.
What the Republican Party should do is to rethink their ideology. Let go of their dogmas. This is a very painful process; I know, I have done it myself. It hurts to let go of the comforting cocoon of knowing the answers to all problems - to let go of the certainty that dogma provides - and step into the terrors of uncertainty and not knowing.
What doesn't work? Lowering taxes on the wealthy and deregulating business and industry. That does not unleash the mighty powers of the free market economy. It enriches the wealthy, harms the environment and the workers, lowers the standard of living of the Middle Classes, and drives many in the Middle Classes into the Lower Classes.
What doesn't work? Enforcing Evangelical morality on the country. This does not call upon God to favor the United States with His Blessings of prosperity; it violates the first amendment that guarantees not only freedom of Religion but freedom from Religion.
What doesn't work? Shrinking the safety nets of Social Security, Medicare and Medicaid, and the various governmental assistances to the poor. These programs do not make people dependent, they help people take charge of their lives.
The Trump Primaries voters have said that endless wars in the Middle East, endless shrinking of public assistance and training, endless shrinking of the government only makes sense to wealthy and upper middle class right wing ideologues, not to real people with real problems.
So, will new leadership arise amongst conservatism to address the real world rather than try to resurrect Reaganism, or Fallwellism, or Ayn Randism? To tell you the truth, I doubt it. At least not in four years. Maybe in eight though.
As to how to change the Primaries season to avoid the catastrophic results of future Trumps? Take power away from the South (and their racism). Have some kind of rotating schedule of states spread out over half a dozen to a dozen dates. Don't have the same grouping of states in the same order every four years. Have Super Delegates that can be a counterweight to populist charlatans. I expect a lot of very smart people are trying figure out how to change the nominating process to produce sane, qualified candidates that represent all of the country.
Trump is more than a whisper that the system is failing, it is a earthquake announcing that the ground has shifted and old systems have failed.