The 58-year-old Hawaii man charged in an alleged assassination attempt of former President Donald Trump authored a book in 2023 calling on Iran to kill Trump and himself.

He wrote that he regretted supporting Trump in the 2016 election, “but I am man enough to say that I misjudged and made a terrible mistake and Iran I apologize. You are free to assassinate Trump as well as me for that error in judgement and the dismantling of the (Iran) deal. No one here in the U.S. seems to have the balls to put natural selection to work or even unnatural selection,” wrote Ryan Wesley Routh in his book, self-published on Feb. 28, 2023.

Routh was charged with two gun-­related crimes in federal court Monday, a day after being spotted hiding in the bushes with a rifle at the former president’s golf course in Florida, according to Reuters.

More charges appear likely, but the initial counts — possession of a firearm as a convicted felon and possession of a firearm with an obliterated serial number — will allow authorities to keep him in custody as the investigation continues, Reuters reported.

The Honolulu Star-­Advertiser asked the Federal Bureau of Investigation on Monday whether Routh’s published assassination request to Iranian agents was ever reported to law enforcement, whether his home in Kaaawa was searched and whether his wife and two children were located and questioned.

“The FBI has nothing additional to provide beyond what FBI Miami SAC (Jeffrey B.) Veltri said in his remarks at the press conference (Monday in Florida),” read an emailed statement from the FBI’s National Press Operations Unit in its Office of Public Affairs in Washington, D.C.

Veltri told reporters in Florida on Monday that the FBI received a tip in 2019 that Routh, who was living in Hawaii, was a felon in possession of a firearm.

The FBI interviewed the tipster but could not corroborate the information about Routh and forwarded the intelligence to law enforcement in Hawaii, Veltri said.

The Honolulu Police Department issued the following statement when asked whether it received a 2019 tip from the FBI about Routh: “The Honolulu Police Department works closely with our law enforcement partners at the federal and state levels. We have been notified of the suspect’s ties to Hawaii and will continue to cooperate with investigators,” HPD Chief Arthur “Joe” Logan said in a statement.

In the final pages of the book, which reads like part-manifesto, part-memoir, blended together with free-flowing ideas about U.S. foreign policy and intervention, Routh writes about how hatred in the world has beat him down.

“As I have reached the ripe age of 57 and I have yet to do anything or any significance or worth in this world and I am certain that this document will likewise go unnoticed and read by anyone,” wrote Routh, who mused he might be assassinated by Pakistan, the Taliban or Russia in the next year for suggesting they send soldiers to fight for Ukraine. “Perhaps fifty years from now, when I am dead and gone, just maybe one of my kids will be bored enough to read this, and hopefully think that maybe I was not as bad a guy as they had thought; but who knows.”

The self-published “Ukraine’s Unwinnable War: The Fatal Flaw of Democracy, World Abandonment and the Global Citizen — Taiwan, Afghanistan, North Korea and the End of Humanity,” was written by Routh. Kathleen Elizabeth Shaffer, his girlfriend and the owner of the house the two shared in Kaaawa, is listed as the editor.

Shaffer, 61, did not answer a Hawaii phone number listed for her Monday.

According to a search of North Carolina court rec­ords, Routh has more than 80 arrests and citations, from felonies to misdemeanors.

Routh was arrested or cited in North Carolina for offenses including speeding, not wearing a seat belt, writing bad checks, unlawfully passing a public-safety vehicle, possession of weapons of mass destruction, forgery, identity theft, drug offenses and carrying a concealed gun, according to online rec­ords kept by the North Carolina Judicial Branch.

On March 24, 2002, Routh was arrested for carrying a concealed gun in Greensboro, N.C.; and on April 12, 2002, he was arrested for possession of weapons of mass destruction.

According to a Dec. 16, 2002, story in the Greensboro News &Record, Routh was arrested after barricading himself in a business during a three-hour standoff, police said.

Routh, 36 at the time, was pulled over during a traffic stop, but he put his hand on a firearm and drove to United Roofing, where he remained barricaded inside, police said.

Routh was charged with “carrying a concealed weapon and possession of a weapon of mass destruction, referring to a fully automatic machine gun.” He was also charged with resisting, delaying and obstructing a law enforcement officer and driving while license revoked, according to the paper.

Routh registered his Camp Box Honolulu, a company that builds small storage structures, as a Hawaii business in January 2019 but let its business registration lapse in January of this year.

Saili Levi, owner of Laie Vanilla Co. LLC, told the Star-Advertiser in an interview that he tried to contract Routh in 2023 to build a mobile display unit for his products to sell them at farmers’ markets and other pop-up events.

Levi saw Routh’s ad in Waikane and reached out to him. After an exchange of text messages, Routh came to Levi’s house to talk through the design and construction.

“At first he seemed like a normal guy. He came to my house after a couple text messages, talked story little bit. He told me he just got back from Ukraine. He was over there helping. … It was kind of odd, but I was trying to get to the point. … He just kind of blurted that out, and I was like, ‘OK, cool, that’s why he was taking a long time getting back to me.’”

Routh gave him a quote, and Levi sent him half the money.

Levi said he reached out to Routh to see the progress on his mobile cart and immediately saw that the quality of product Routh alleged he could build and what he actually produced were not close. Levi said he told him to “fix this or give me my money back.”

Routh then referred Levi to his company’s customer policy and sent him an email Aug. 1, 2023, detailing his displeasure with Levi and the Oahu he returned to after being in Ukraine.

“I spent 5 months in Ukraine last year and 3 months there this year, and 2 weeks in DC and 2 weeks in Taiwan this year volunteering and trying to supply thousands of Afghan soldiers to help win the war and I spent thousands of dollars supporting freedom, human rights and democracy around the world and I come back to (BS) such as this. I have been home less than a month and this is the quality of humanity that I must face; ungrateful, selfish rich people; blows my mind,” wrote Routh. “It is sad that the best humans among us are sacrificing themselves and getting killed on the front lines while the people that do not care live happy carefree lives; very sad. Perhaps I would be happier dead on the front lines than dealing with rich people in fancy cars as I drive old broken down vehicles and hoping to keep my account out of the negative and hoping for food to eat. China and Russia will certainly win at this rate. You disappoint me as a human.”

Levi said he recognized what he was dealing with and left reviews online warning other customers of Routh’s behavior.

“When I got the email, I thought, ‘Oh, this guy is off,’” he said.