Mahmoud Khalil wants to take the case against his deportation all the way to the Supreme Court.

If the justices accept it, they’ll be deciding one of the oldest and most controversial questions in American politics — a dispute more than 200 years old.

Khalil is not an American: He’s a Syrian-born Palestinian, here legally.

He’s opposed to the policies of the democratically elected government of our country, and he’s used the freedoms and privileges afforded to him on American soil to agitate for policies that would favor Hamas over Israel.

President Donald Trump saw no reason why a guest should be able to undercut his host in this way, so ICE began deportation proceedings — he was taken into custody at Columbia University, where he was a graduate student. 

And then the courts got involved.

A New Jersey judge said ICE had to release Khalil because, in the judge’s opinion, the case against him was likely to fail in the end on First Amendment grounds, and in the meantime he should be free to continue his Palestinian activism. 

Judges in other cases have ruled noncitizens do have First Amendment free-speech rights, but a federal appeals court in Pennsylvania overturned the earlier decision that released Khalil from detention.

The big question still hasn’t been answered: When can America deport a foreign political activist? 

If Khalil were a Russian demanding America end support for Ukraine, Democrats would in all likelihood be eager to have him expelled — though an administration like Joe Biden’s might look for an espionage angle to justify deportation.

Trump’s administration is not looking for pretexts: It’s tackling the principle at the heart of the matter.

America’s earliest presidents saw the question the same way Trump does.

George Washington famously proclaimed America neutral in the conflict between revolutionary France and Great Britain, but France deployed agents — including its de facto ambassador to America, Edmond-Charles Genêt — to organize opposition to Washington’s policy and drag America into the war.

The French revolutionary strategy was to go over Washington’s head and appeal directly to the American people, by setting up what we would now call grassroots activist groups and even the political organs resembling the beginnings of a political party, called “Democratic Societies.” 

Washington even believed these radical, pro-French groups were responsible for political violence, including the 1794 Whiskey Rebellion.

Thomas Jefferson was madly in love with the French Revolution — he wrote in one letter he would rather see half the earth desolated and every country reduced to just an Adam and an Eve than let the French cause fail.

Yet even Jefferson recognized that Genêt had gone too far and was subverting the government Americans had chosen for themselves. 

The only reason Genêt was ultimately not deported was because the unstable revolutionary government in France had changed: The new authorities stripped Genêt of his diplomatic role and intended to execute him if he went back home.

The problem was much bigger than Genêt, however, and Americans expressed their opposition to French radicalism by electing John Adams rather than Jefferson as president in 1796, along with a Congress dominated by anti-French Federalists. 

To tackle ongoing foreign subversion, Congress passed, and Adams signed into law, the Alien and Sedition Acts.

Although liberal historians have subsequently demonized these laws, the restrictions they placed on foreigners’ political activities were justified. 

In fact, one of the three controversial laws — the Alien Enemies Act — is still on the books: It gives the president the broad power to deport any foreigner from an enemy country during wartime. 

The Alien Friends Act, which specified the president’s powers to remove foreigners during peacetime, didn’t survive the election of Jefferson and his party’s congressional majority in 1800.

But other laws since which have reaffirmed presidential authority to expel foreign political activists in times of peace, and they remain in force.

Immigration law, for example, includes a provision allowing removal of “an alien whose presence or activities in the United States the Secretary of State has reasonable ground to believe would have potentially serious adverse foreign policy consequences.”

It’s a commonsense policy, and the power has to rest with the executive branch — Congress can’t legislate for every circumstance, and judges should virtually never set national-security policy or usurp the elected president’s role in making foreign policy.

Middle East policy is something for the American people to debate among themselves, especially when passions run as high as they did in the days when the French Revolution polarized American politics.

Mahmoud Khalil does not have a right to set America’s policies, even through the indirect means of political organization and speech.

And if the Supreme Court takes this case and gets it wrong, it won’t be the First Amendment that’s saved — but our self-government as a distinct people that’s lost.

Daniel McCarthy is the editor of Modern Age: A Conservative Review.