In preparation for marriage, I have been reading Fulton Sheen’s classic Three To Get Married, which interweaves meditations on matrimony, fatherhood, and motherhood with sophisticated Trinitarian theology. In a chapter titled “The Unbreakable Bond,” Sheen reflects on the indissoluble nature of marriage and connects it to the other vows that undergird human society:

It [the vow] may be hard to keep, but it is worth keeping because of what it does to exalt the character of those who make it. Once its inviolable character is recognized before God, an impulse is given to self-examination, the probing of one’s faults, and new efforts at charity. It is too terrible to contemplate what would happen to the world if our pledged words were no longer bonds. No nation could extend credit to another nation if the compact of repayment was signed with reservations. International order vanishes as domestic society perishes through the breaking of vows. […] Once we decide, in any matter, that passion takes precedence over truth and erotic impulse over honor, then how shall we prevent the stealing of anything, once it becomes “vital” to someone else?

Sheen is making a point central to social conservatism. The keeping of promises, the maintenance of trust, the sacredness of one’s word. These are some of the noblest values in the conservative firmament—which is why it has been so dispiriting watching conservative commentators ignore these truths and tout Donald Trump, a man who tramples on vow-keeping.

The debate last night underlined the reasons why Donald Trump’s character and temperament should be disqualifying in the eyes of conservatives. Even those of us most worried about a Clinton presidency need to wield a plausible exit threat, else what influence can we really exert over any party? And if Donald Trump is not reason enough to follow through on this threat, what possible Republican candidate would be? David Duke?

Trump’s policies, such as they are, usually come down to America breaking its promises. In the debate, he doubled-down on his previous pledge to back out of defending our NATO allies (who came to our defense after 9/11). Later in the debate he casually said we can’t defend Japan, another nation with whom we have a mutual defense treaty. This promised perfidy is of a piece with his rhetoric about tearing up deals and starting trade wars. He then brushed off the idea that stop-and-frisk policing was unconstitutional—not by taking the chance to give us any sense of how he understands the Constitution, but with flat denials. It seems that, like America’s treaties, the Constitution is just another document waiting to be renegotiated.

Donald Trump’s appeal is bound up in his transgressive persona. He does what is Just Not Done. But conservatives who spin this as simply “shaking up the corrupt norms of a stale political class” are being naïve or willfully obtuse. Trump does not care from where a norm comes. His consistent approach—as a businessman, as a showman, as a Democrat, and now as a Republican—is to violate whatever norm is in place, as a demonstration of his own power.

For forty years, every aspirant to higher office in the United States has released his or her tax returns. This is not a politically correct shibboleth, this is not an arcane tradition, this is a norm with a clear and pressing reason behind it. And Donald Trump bucks it, on the flimsiest of pretexts. If he wins the Presidency after doing this, no candidate will feel obliged to follow this norm—in an instant, a check on the powerful built up by use and custom would be torn down.

Hillary tried to emphasize Donald Trump’s lies, exaggerations, and absurd boasts. But playing fast-and-loose with the truth is hardly something that makes Trump unique on the political scene. What were most disturbing in his first debate performance were the times he chose to acknowledge his past dishonors brazenly, to frame them as matters of pride. This was how he reacted when confronted about his refusal to release his tax returns (“that makes me smart”), his bilking of contractors (“I was unsatisfied with his work”), and his tax-dodging (“it would have been squandered”).

Donald Trump seems to think that backing out of agreements is laudable, as long it helps him get ahead. But any churl can break a vow. What takes character, in politics, business, or marriage, is to make a vow and keep it, come what may. Trump left open for Clinton a line that should by rights be a conservative rallying cry, “It is essential that America's word be good.” Alack the day the GOP lost the right to say that!

This year is a chance for conservatives to demonstrate that we actually care about America’s honor. We should not endorse a man who built his career and his campaign on faithlessness. We should also take it as an opportunity for spiritual growth, letting the candidates serve as negative examples that spur us to be better. While we research which third-party and down-ballot candidates we can vote for in good conscience, we should also seek out chances to do corporal works of mercy. Perhaps this election can repudiate not only the offerings of the major parties, but also the whole logic of denigrating truth and integrity. And we, in the meantime, can get to work feeding the hungry, sheltering the homeless, and visiting the imprisoned.

Alexi Sargeant is assistant editor of First Things.