Donald Trump’s victories in New Hampshire, South Carolina, and now Nevada should be a wakeup call to all who oppose him. The time has come for us to unite – and to prioritize Trump’s defeat over other electoral considerations. If you are a conservative or libertarian who cares about upholding the Constitution and limiting the power of government, your main goal in this GOP nomination campaign must be to stop Trump.

I. Why Trump is YUGELY Awful.

I am not going to go over all the reasons why Trump would be a horrible nominee in detail. That has been done already by others, such as Peter Wehner, and the participants in the National Review symposium on Trump.

I will only highlight a few of The Donald’s lowlights. Trump openly advocates massacring innocent civilians. He wants to use bogus lawsuits and FCC censorship to suppress the speech of his critics, and recently pined for the “old days” when his supporters would have been allowed to beat protestors to the point where they “have to carried out on a stretcher.” He has lobbied for the government to condemn a widow’s home so he could use it to build a casino parking lot. He has utter contempt for constitutional property rights, and other constitutional limitations on government power. He wants to deport millions of people to lives of Third World poverty and oppression, including hundreds of thousands of children born in the United States, who have never known any other home. And he would engage in massive discrimination on the basis of religion.

A man who advocates such things must not be elected president of the most powerful nation in the world, and he must not be allowed to become the nominee of a major party. Blocking him is far more important than ensuring the victory of any one other candidate that we might happen to prefer. The differences between the other viable candidates are modest compared to the evil represented by Trump. Trump many not really believe or want to act on some rhetoric. But it would be dangerous to take that chance. Even if it is all an act, a triumphant Trump might well be conclude that the script that got him in the White House will also help him stay there and consolidate his power.

History shows that even a failed nominee can sometimes have a significant impact on the future course of his party, as witness the cases of Barry Goldwater in 1964 and George McGovern in 1972. We do not want to see a GOP remade in in Trump’s image – even partially. There is much wrong with the party as it is; it would not have been such fertile ground for Trump otherwise. But the party will not be improved by Trump’s program of making it more like the far-right, neofascist parties of Western Europe. Like Trump, those parties combine xenophobia with big government policies on both economic and social issues, and contempt for limits on state power.

II. What is to be Done?

At least in the short term, we cannot eliminate the ignorance and xenophobic bigotry that drives much of Trump’s support. But we can work to ensure that all those who oppose Trump within the GOP unite under the same flag.

At this point, it seems highly likely that none of Trump’s opponents can defeat him if they all stay in the race. In that event, he can continue to take the lion’s share of delegates by winning 30-40 percent of the vote in most states. On the other hand, Trump is highly vulnerable in a 1 on 1 race, because a large percentage of the GOP electorate considers him fundamentally unacceptable, and very few supporters of other candidates see him as their second choice. The more other candidates drop out, the worse his position becomes. The solution here is obvious: in order to defeat Trump, we must get all but one of the other candidates out of the race as soon as possible – before Trump is able to rack up a big lead in the delegate count.

Who should be the one? It’s pretty obvious that Ben Carson’s campaign is hopeless, at this point. John Kasich is an admirable candidate in a number of ways. But it’s also clear that he has very little if any chance of winning. He polls at only about 10 percent in most national surveys, and trails Trump even in his home state of Ohio. Barring multiple miracles, Kasich is not going to be the nominee.

Ted Cruz has better odds than Kasich, and even managed to beat Trump in Iowa. I am far from being a big Cruz fan myself. Still, I can understand why many conservatives – and even a few of my libertarian friends – support him. But, whether you like him or not, he has only a small chance of success. He has had great difficulty attracting much support beyond his conservative evangelical base. This, and other factors, make it unlikely he can prevail in the crucial “winner take all” states that come after Super Tuesday, where he must do well in order to secure the nomination. In addition, Cruz will have great difficulty unifying the anti-Trump sections of the GOP behind him because many of the party’s leaders and activists absolutely despise him, and some (wrongly, in my view) might even see Trump as the lesser evil of the two. We can argue about who is to blame for the hostility between Cruz and the “establishment.” But there is no doubt that it exists, and that it hurts his chances to become a unifying figure.

That leaves Marco Rubio as the best choice. Rubio is acceptable to a wide range of conservative and moderate Republicans, and to both the Tea Party wing and the establishment. For what it’s worth, he also polls much better than the other candidates in a potential general election matchup with Hillary Clinton (Trump is, by contrast, hugely unpopular with general election voters).

I am not much more of a Rubio fan than I am a Cruz fan. A Rubio administration is likely do many things that I would decry. But he is vastly better than Trump on nearly all the issues that make the Donald horrendously awful. And he has by far the best chance of defeating him in a one on one race.

But Rubio is unlikely to get the chance unless the rest of the field clears out; preferably sooner, rather than later. Therefore, I urge all potential anti-Trump GOP voters to cast their ballots for Rubio. And I urge the other candidates to DROP OUT NOW and endorse him. If they truly care about the limited government principles they claim to support, they can serve that cause best by leaving the race and throwing their support to the candidate who has the best chance of blocking Trump. It is far better to fall on your sword for the sake of the cause, than to be a sore loser who takes the cause down with him. Those who do the right thing might even advance their longterm career prospects. If you are going to lose anyway, as Cruz and Kasich are highly likely to do, you will be better off if you earn the gratitude of party activists in the process, than if you store up enmity among the many who will rightly blame you for a Trump victory.

I am not naive enough to expect either voters or politicians to do the right thing as a matter of course. If they did, we would not be in this situation to begin with. The hour is long, and the opportunity to set things right might easily be missed – yet again. But it is not yet too late to dump Trump in the dustbin of history where he belongs.

UPDATE: I should perhaps stress one point that should have been clear already, but perhaps I did not make it so. I think Rubio dropping out and endorsing Cruz would also be a significant improvement over the status quo, just as the reverse would be. While dislike a good deal of Cruz’s platform (as well as a good deal of Rubio’s), I think he is far preferable to Trump. There is a plausible argument that Cruz would have a better chance in a one on one race with Trump than Rubio would. I am skeptical, however, for reasons discussed above: Cruz is relatively weak in the crucial winner take all states, and he is likely to have greater difficulty uniting the party behind him. But I acknowledge that I am less confident about this point than about the other steps in my argument, in part because it is not easy for survey data to fully predict the impact of a sudden, massive shift in the nature of the race, and harder still to compare two such hypothetical scenarios against each other (Cruz dropping out to back Rubio vs. the opposite).