If you’re wondering why Republicans are in such a difficult fix today, allow me to remind you of a time back in the 1990s when Israeli leader Shimon Peres was trying to convince supporters of Israel that the Oslo peace process would work. Peres would retell the fable about the scorpion and the frog. It’s the one about a scorpion who convinces a skeptical frog to ferry him across a river and assures him that his fears that he will be stung are foolish since doing so would drown them both. But midway across the river, the scorpion stings the frog anyway. As they sink, the frog asks why he did it. The scorpion answers that this is the Middle East (the traditional version has the scorpion saying that it was just in his nature). Peres’ point was to say that it was time for people to start acting rationally and live in peace. But the story perfectly illustrated why his faith in the Palestinians wanting peace was a delusion. Israel’s foes were too dedicated to its destruction to do the rational thing and make peace even on generous terms. So the war continues to this day.

What does this have to do with the Republican Party in 2016? More than you think.

On the day after the Nevada Republican caucuses, it’s now clear that Donald Trump is sweeping his way to the GOP presidential nomination. Marco Rubio and Ted Cruz are still telling us they can win, and their supporters can still come up with theoretical scenarios that will allow them to do that. But let’s face it. If the name of the current frontrunner were not Donald Trump, a person that is despised and feared by much of the political class as well as the mainstream of the Republican Party, would any sane pundit or analyst not concede that the nomination was sewn up? I don’t think so.

In response, some smart writers like our John Podhoretz are calling for Rubio and Cruz to start attacking Trump rather than sitting back and waiting for him to implode on his own. That’s good advice. Trump has benefitted enormously from the fact that all of his major competitors have concentrated their fire on each other rather than him. But let’s not kid ourselves about this either. It’s not as if no one has been criticizing Trump. The problem is that the scorn that has been directed at him hasn’t affected his support in the least. To the contrary, it’s growing every week as Nevada proved. At this point, there is no reason to believe that even a concentrated plan of attack from his two main rivals would convince a critical mass of GOP voters that Trump’s “punch him in the face” style isn’t what the country needs. They’ve already told us loud and clear they don’t care about Trump’s inconsistencies and inability to provide any details about how he will “make America great again.” When are we going to start listening to them?

Nevertheless, some are also still talking about a consolidation of the field that will provide the presumed majority of Republican voters that don’t want Trump with a way of stopping him from winning primaries and caucuses with a plurality. That’s logical, but there is one big problem with any scenario along those lines.

And that’s where the frog and the scorpion come in.

It’s obvious to just about everyone who follows politics that Ohio Governor John Kasich hasn’t a path to the Republican nomination. It’s not even clear that he can even win his home state primary on March 15. Even Kasich acknowledged that he doesn’t “know if my purpose is to be president.”

Ben Carson has also been riding the caboose of the campaign, and it’s not clear his candidacy has any purpose other than to give him a personal platform.

But neither Kasich nor Carson are showing any willingness to get out of the race even though they have to know that their doing so in a timely manner would be the only way to stop Trump. Yet even if that were to happen, either before next week’s Super Tuesday, SEC primary or at least before March 15, it probably wouldn’t be enough to allow either Rubio or Cruz to start beating Trump.

As I noted after the South Carolina primary, Trump has stolen the evangelical and religious Christian vote from Cruz. He’s also beating him among Tea Party and very conservative voters. In other words, Cruz is finished.

Rubio has a more viable scenario for victory since he could, at least in theory, rally the entire mainstream GOP behind him and hope to finish ahead of Trump. But as the first four contests have demonstrated, that slice of the Republican pie is a lot smaller than it was four and eight years ago when Mitt Romney and John McCain won the nomination. There is also the inconvenient fact that all of his Marcomentum and endorsements from former Jeb Bush supporters haven’t enabled him to get close to Trump in Nevada or the polls of the states that will vote next week. Trump’s popularity and the growing impression that he’s the inevitable winner means that even if the race gets down to just the top three, Trump is still likely to finish first.

In other words, Rubio’s prospects aren’t actually much better than those of Cruz.

National Review’s Jonah Goldberg confronts this reality and has a bold suggestion today. He says the only way to stop Trump is for Rubio and Cruz to join forces. He knows this is unlikely, but they have no alternative if they want to prevent their party from being hijacked by a billionaire who isn’t a conservative.

I agree. But it won’t happen because of that frog and scorpion problem.

I first wrote about the need to start a stop Trump movement as far back as August and wrote in December that the quartet vying for the lead in the establishment lane (Rubio, Kasich, Bush and Chris Christie) couldn’t wait until after New Hampshire to settle on just one of them. But the egos of each of these politicians won’t allow them to concede that they weren’t the party’s one true savior to which the others should bow. Incredibly, that’s still true now for Rubio, Cruz, Kasich and Carson.

Part of it is the enormous energy, money and infrastructure that go into a presidential campaign. It’s not easy to give up such a ship even when it is sinking, and these vessels aren’t abandoned until, as with Bush in South Carolina, the water is already over their heads.

The remaining candidates won’t join a stop Trump movement if they aren’t at its head because a) they think they are the one true alternative and b) they think the others are unworthy, and they’ve expended too much money and credibility on tearing them down.

Cruz may know in his heart that Rubio would be a hundred times better than Trump but can a man who says he will never compromise on principle swallow his pride and back the Florida senator after damning him as a craven creature of the establishment? If Cruz has taught us anything about himself, it is that he would rather go down with the ship (or shut down a government) rather than make even the most reasonable deal.

The same appears to be true of Kasich and Carson, though latent delusions about victory may also play a role here for them and Cruz. To be fair, the same can be said about Rubio, who wouldn’t step aside for one of the others either because at the moment, he is ahead of them in the polls.

At this point, the proverbial smoked filled room in which hardened political professionals could make a rational choice is looking good to many Republicans. But there is no way to force any of the candidates into one or to make them abide by the judgement of wiser and cooler heads. Instead, Republicans are stuck being led by frogs and scorpions. The quartet of non-Trumps will continue fighting each other until it is too late because it is in their nature to do so. And that, and not any statistical analysis of the vote, is why there doesn’t appear to be a way to stop Donald Trump from being the Republican presidential nominee in 2016.