The gunman was identified by CBS as Gavin Eugene Long. Multiple reports linked Long to homegrown hate groups. The Wall Street Journal, citing sources, said he belonged to an antigovernment group called the New Freedom Group. MSNBC reported he belonged to a different group, called the Sovereign Citizens.

If Alexander Hamilton were alive today, I am certain he would be (1) grateful that the nation honors him by retaining his portrait on the $10 bill, (2) bemused by the Broadway rap play based on his life, and (3) planning to vote for Hillary Clinton.

Donald Trump would have reminded Hamilton of Aaron Burr, his political nemesis and the man who would ultimately kill Hamilton in a duel. Like Trump, Burr had an outsized, narcissistic personality. Fidelity to principle never stood in the way of Burr’s self-advancement. His defining moment came in the presidential election of 1800, when he reneged on a promise to serve as Thomas Jefferson’s vice president and tried to seize the presidency for himself.

Burr’s attempt to leapfrog over Jefferson put Hamilton in a bind. Hamilton was not a member of the House of Representatives when it convened to resolve the election, but he was an influential leader of the Federalist Party who could sway votes in the House. Many Federalist representatives were tempted to vote for Burr (and some did) because Jefferson was an ideological anathema to them. To mention only one of a variety of principled differences: The Federalists favored a strong national government, and Jefferson wanted to return power to the states. Asking a Federalist to vote for Jefferson is not that different from asking a conservative Republican to vote for Hillary Clinton today.

Yet that is just what Hamilton did: He supported Jefferson over Burr. Writing to Harrison Otis, leader of the Massachusetts House delegation, Hamilton noted that “Mr. Jefferson, though too revolutionary in his notions, is yet a lover of liberty and will be desirous of something like orderly government—Mr. Burr loves nothing but himself…” Hamilton concluded that any deal the Federalists tried to strike with Burr would never bind Burr, who “thinks of nothing but his own aggrandizement,” and whose controlling passion is “ambition.” With remarkable foresight, Hamilton saw that a Democratic-Republican administration under Jefferson would allow the Federalists to remain a principled party of opposition, ready to return to power when the Democratic Republicans faltered. If the Federalists supported Burr, however, “they adopt him and become answerable for him.”

Republicans who vote for Trump face the same dilemma. If elected, Republicans would be blamed for his failures. To support Trump, we must sacrifice our principles and reconcile our minds to his. Better we should follow Hamilton’s example and support an opposing party whose principles we reject—and remain a principles party of opposition.