This campaign season has offered an unexpected form of reality television entertainment: Watching the light of discovery and calculation in Donald Trump’s eyes when he is presented with difficult policy issues, apparently for the very first time.

Abortion is the current case in point. In the late 1990s, Trump supported the legality of partial-birth abortion. For a few hours on Wednesday, he endorsed criminal sanctions against women who have abortions.

On this issue, Trump has been to the left of Harry Reid (who voted for a partial-birth abortion ban) and to the right of Mike Huckabee (who has consistently rejected punishment for women who have had abortions). And Trump is utterly incapable of defending either position. He shows no capacity for ethical reasoning — balancing claims about the moral and legal value of nascent life against claims about autonomy and choice.

If that seems harsh, let’s go to the transcript of MSNBC’s Chris Matthews trying to corner Trump on criminalization. Asked if this is the logical consequence of pro-life views (it isn’t), Trump doesn’t advance an argument about religion, morality and the role of law (other than to call attention to Matthews’s Catholicism). At the outset, Trump observes that “people in certain parts of the Republican Party and conservative Republicans would say, ‘Yes, they should be punished.’ ” Trump eventually embraces what he thinks a social conservative would say.

In fact, this is not the pro-life position. It is the left’s stereotype of the pro-life position. “No pro-lifer would ever want to punish a woman who has chosen abortion,” responded Jeanne Mancini , president of the March for Life. “This is against the very nature of what we are about. We invite a woman who has gone down this route to consider paths to healing, not punishment.”

Republican presidential candidate Donald Trump stirred up controversy when he said there should be "some sort of punishment" for women who have abortions. Here's a look back at how he "evolved" into his pro-life views. (Jenny Starrs/The Washington Post)

Trump ended up hurting the pro-life cause by reviving a stereotype of harshness. And that was part of a pattern.

In the immigration debate, the restrictionist side makes some serious arguments for prioritizing control of the border and for an immigration system that puts greater emphasis on skills. I generally don’t find such arguments compelling, but they are worth debating.

Trump has not, however, made this case in any serious or systematic way. Instead, he has embraced an anti-immigrant caricature. Illegal immigrants, he says, are disproportionately criminals and rapists. The Mexican government is purposely sending criminals across the border. When two Trump supporters beat up a homeless Hispanic man in Boston, Trump called them “very passionate.” He retweeted that Jeb Bush “has to like the Mexican illegals because of his wife.”

When Trump eventually loses — as he certainly will in the primaries, at the convention or the general election — the movement to restrict immigration will be left as a stereotype of exclusion and bigotry.

Trump has had a similar malignant influence on debates concerning the war against terrorism. There is no doubt that the United States and Europe face a heightened threat from returning Islamic State fighters and from homegrown terrorists inspired by the Islamic State. Additional measures will be required — in the Middle East and at home — to preempt these threats.

But Trump has chosen to inhabit a cruel and counterproductive parody of toughness. He calls for banning all Muslim immigrants. He would conduct the war against terrorism with war crimes, such as killing the families of terrorists. He calls Syrian refugees fleeing violence the “ultimate Trojan horse.” He entertains the possibility of using nuclear weapons against the Islamic State — which would, of course, also kill everyone the Islamic State oppresses.

This stereotype of strength actively undermines the war against terrorism by alienating Muslim allies and cultivating mistrust in Muslim communities.

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For many of Trump’s supporters, this extreme and unpredictable use of language is part of the appeal. He doesn’t employ the careful words of a politician. He is so appealingly unprepared. So refreshingly ignorant. So disarmingly half-baked.

But the durability of Trump’s appeal creates a conundrum for many Republicans. For decades, some of us have argued that the liberal stereotype of Republicans as extreme, dim and intolerant is inaccurate and unfair. But here is a candidate for president who fully embodies the liberal stereotype of Republicans — who thinks this is the way a conservative should sound — and has found support from a committed plurality of the party.

If the worst enemies of conservatism were to construct a Frankenstein figure that represents the worst elements of right-wing politics, Donald Trump would be it. But it is Republicans who are giving him life. And the damage is already deep.

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