Neil Young is not mincing words when it comes to President Donald Trump. The singer wrote an open letter to Mr. Trump, posted on his website, and with the first sentence, it's apparent this is far from a love note: "You are a disgrace to my country," Young writes.

"Bragging about the U.S. economy does not disguise the fact that the numbers today are what you inherited almost 4 years ago," Young continues, referring to Mr. Trump's recent spat over President Obama's role in the financial recovery.

On Monday, Mr. Obama tweeted: "Eleven years ago today, near the bottom of the worst recession in generations, I signed the Recovery Act, paving the way for more than a decade of economic growth and the longest streak of job creation in American history."

Get Breaking News Delivered to Your Inbox

Later that day, Mr. Trump issued a rebuttal, tweeting: "Did you hear the latest con job? President Obama is now trying to take credit for the Economic Boom taking place under the Trump Administration. He had the WEAKEST recovery since the Great Depression, despite Zero Fed Rate & MASSIVE quantitative easing. NOW, best jobs numbers...."

Neil Young was born in Toronto, Canada, and moved to the U.S. as a young adult. He revealed in January he had registered to vote as a Democrat. Thos Robinson/Getty Images for The New Yorker

Young doesn't refer to that spat in his open letter, but he does draw a direct comparison between Mr. Trump and his predecessor, writing: "Our first black president was a better man than you are."

He also criticizes the current administration's "mindless destruction of our shared natural resources, or environment and our relationships with friends around the world," which Young called "unforgivable."

The songwriter, who grew up in Canada, recently became a U.S. citizen. He posted on Instagram in January that he registered to vote as a Democrat. In his letter, Young refers to the United States as "my country," and told Mr. Trump it is not "a green on one of your branded golf courses that you can ride around on and damage so that other players cannot shoot straight."

He also refers to his hit 1989 song "Keep On Rockin' In The Free World," which he says is not a song Mr. Trump can play at MAGA rallies. "Perhaps you could have been a bass player and played in a rock and roll band," Young writes. "That way you could be on stage at a rally every night in front of your fans, if you were any good, and you might be..."

Young said every time the song does play at a Trump rally, "I hope you hear my voice. Remember it is the voice of a tax-paying U.S. citizen who does not support you. Me." This is not the first time Young has told Mr. Trump to stop using his music. In 2015, the rocker's manager said the Trump campaign "wasn't authorized" to use "Rockin' in the Free World."

In the letter, Young goes on to say he does not blame Trump supporters because he supports their right to express themselves.

"U.S. justice is ours — not yours," Young writes to the president. Then he turns his attention to a candidate he likes better.

"One of your opponents has answers I like. He is aiming at preserving our children's future directly. He is not popular with the democratic establishment because unlike all the other candidates, he is not pandering to the industries accelerating Earth's Climate Disaster, the end of the world as we know it. he is truly fighting for the USA."

"His initials are BS. Not his policies," Young writes, revealing that he is referring to Bernie Sanders, whom he also supported four years ago. "We are going to vote you out and Make America Great Again."

The 74-year-old musician signs off with the phrase "Children of Destiny," the title of his politically-charged song from 2017, in which he sings: "Stand up for what you believe/ Resist the powers that be," and "When money matters most and war is good for gain/ The capital is yours, the people feel the pain."