Perhaps Hillary Clinton’s most famous remark ever was her insistence in 1998 that the real story of the Monica Lewinsky affair was “this vast right-wing conspiracy that has been conspiring against my husband since the day he announced for president.” A decade later, emails as secretary of state show that she still has an insatiable appetite for bizarre conspiracy theories to explain away bad news.

Set aside the questions about Clinton’s use of a private email server and her mishandling of classified information: The content of her mail exposes the fact that the advice Hillary seeks out from her most trusted confidants is often just plain weird.

One email released this week involves two top figures in Clintonworld: David Brock and Sidney Blumenthal. Brock founded Media Matters, a group that acts as both a rapid-response team and a digital spin room for Democrats. Blumenthal is a longtime Clinton hatchet man.

The message is, in its entirety, utter lunacy. On Oct. 24, 2010, Blumenthal sent Clinton a note from Brock titled: “Memo on Impeaching Clarence Thomas.” It concentrated on the claims by one woman of having been romantically involved with the Supreme Court justice prior to his confirmation.

Why was the sitting secretary of state reading a memo on impeaching a Supreme Court justice — for a decades-old affair, no less? There is no good answer, but it’s far from the only strange and conspiratorial nonsense to show up in Hillary’s emails.

Clinton values Blumenthal’s advice so much that, after President Obama forbade her from hiring him at the State Department, she put him on the Clinton Foundation payroll instead and used him as a top adviser anyway.

Blumenthal’s unreliability bothered other Democrats. The New York Times reports that some Clinton aides “viewed him suspiciously for his conspiratorial bent; some nicknamed him ‘G.K.,’ for grassy knoll” — as in the knoll at the center of endless Kennedy assassination conspiracy theories.

A wise public official would keep Blumenthal at a distance and view everything he said with skepticism. Hillary did the opposite. She absorbed his guidance, shared it with her immediate staff (and even some American diplomats) and urged him to keep the emails and phone calls coming.

And he did.

One go-to topic for liberal conspiracy theorists these days is Israel and the idea that American Jews might be loyal to the Jewish state, not the United States. Blumenthal — whose son is a maniacally anti-Israel liberal activist — doesn’t think much of Israel, either.

In one email, Blumenthal told Hillary that Israeli Prime Minister Benjamin Netanyahu “is stage managing U.S. Jewish organizations (and neocons, and the religious right, and whomever else he can muster) against the administration. AIPAC itself has become an organ of the Israeli right, specifically Likud.”

The idea that American Jews were being controlled by a foreign capital was a recurring theme for “Sid Vicious.” In November 2010, he wrote that Malcolm Hoenlein, the head of the Conference of Presidents of Major American Jewish Organizations, “has been raising money hand over fist for the Republicans through [then-Rep.] Eric Cantor, now his vehicle. The donors are many of the same US donors to Bibi and Likud. Implications obvious.”

Blumenthal also sent Clinton analyses on Iran by the long-discredited conspiracy theorist Gary Sick, who rose to fame with a sloppy and false book claiming that Ronald Reagan had arranged for the Iranian hostage crisis to drag on until he’d won the 1980 election.

Sick’s analyses had their own strangeness: He claimed in 2010 that those who took a tough line on Iran were just “dying to repeat Iraq,” and that the Iraqi people had suffered under anti-Saddam sanctions because of “a vindictive United States.”

Clinton sought Blumenthal’s take on domestic politics, too — and it was just as odd. House Speaker John Boehner, he wrote, is “despised” by the conservative base because “He is louche, alcoholic, lazy, and without any commitment to any principle.”

Perhaps conservatives think Boehner is unprincipled, but with “louche” and “alcoholic,” Blumenthal was projecting his own peculiarly personal (and irrelevant) dislike for Boehner onto others.

All this would be more entertaining if not for the clear lesson here: No matter what laws or procedures stand in the way, Hillary Clinton, if elected president, will be listening to Sidney Blumenthal.

The only question is: Would she wear her tinfoil hat when she takes the oath of office?