If Trump captures the nomination, it will also be a disaster for the relationship of pro-lifers with the Republican Party. Unless Trump picks someone with the most rock-solid pro-life credentials as his running mate, it is very likely that a solid chunk of important pro-life activists will seek out a viable third party candidate, or throw their support behind the nominee of a tiny pro-life party, like the Constitution Party. In fact, there is good reason to believe that a Trump nomination may bring out a retired Republican congressman to run on the Constitution Party’s ticket. Trump may say he is against abortion, but his conversion on the issue is far less convincing than those of previous nominees like Mitt Romney or George H.W. Bush.

The Republican Party has never exactly fought with everything it had to confirm enough originalists to overturn Roe V. Wade and thereby return lawmaking on abortion to the states. But in order to keep its coalition from really cracking up, it has to at least be a plausible vehicle for the aspirations of these voters. With Trump at the top, it won’t be.

For Republican elites who may be pro-choice and for grassroots activists who believe they cannot support a party that wobbles on this issue, a Trump nomination shatters a mutual illusion: that the pro-life grassroots and the Republican elite need each other. In fact, absent major scrambling by a third party candidate, Trump’s nomination all but guarantees that conservatives will be reduced to a tiny rump on a consolidated, progressive Supreme Court.