A complete list of those President Donald Trump has tweeted "Happy Birthday" to in 2017 includes his wife, son, three branches of the United States military and ... Lee Greenwood. "WTF" is a perfectly acceptable response.

The "God Bless the U.S.A." singer calls Donald Trump a friend, telling Taste of Country that the president is a big country music fan. Greenwood's wife, Kimberly, worked for Trump for 21 years when he owned the Miss Universe organization (Kimberly Payne was Miss Tennessee USA in 1989). Donald Trump's Friday morning tweet (Oct. 27) is his second that mentions Greenwood, who performed for the 2017 inauguration in January, later posing with his wife and the president for a photo. He's actually the ninth different president the 75-year-old country singer has met and/or performed his song for, but keeping it apolitical has been tricky.

"I was very resistant to that from the very beginning. I wrote it in 1983 and during the 1984 convention everybody really wanted us to get involved in that, and I declined both conventions, Republican and Democratic," Greenwood shares before boarding a plane to Tunica, Miss., to join his wife for the Miss Mississippi pageant (she's still executive director of the pageant in Tennessee, Georgia and Mississippi). "It wasn’t until Ronald Reagan's camp asked me if I would let them use ‘God Bless the U.S.A.’ in the president’s life film until I think I became tied with that side.” (He identifies as a Christian conservative.)

The heroically sentimental ballad would become a Top 10 hit on Billboard's Hot Country Songs chart in 1984, and reemerge as a Top 20 after the terrorist attacks of Sept. 11, 2001. Greenwood has seven No. 1 country hits and over a dozen more that reached the Top 20, but it's this song that will forever be his most famous. It's endured because he didn't write for one particular time in history, he says.

"I wanted something that would unite the country and I just hit the target."

After tweeting at the wrong Lee Greenwood, President Trump mentioned the hit song in a birthday tweet to the singer. This is curious, but not necessarily something he did as a way to rally his base. "I spoke to him several times, of course, before he ran for president and again when he ran for president, and of course he was very out front of using 'God Bless the U.S.A.' as a campaign song and that made me very proud," Greenwood says. "I love the model ‘Keep America Great’ and ‘Let’s make it great again’ so I’m all on board for that. That’s great."

A lot of ink and blog space has been dedicated to the tie between country music and conservative politics, and from there to President Trump. Vocal supporters of the country's 45th president include Greenwood, John Rich, Charlie Daniels, Justin Moore and Loretta Lynn. Conversely, a call from mainstream publications like Rolling Stone for country artists to denounce the president or his policies has been met with silence, most repeating the axiom that to do so would be career suicide. That's not to say artists aren't watching, however — Nash Country Daily put together a nifty list of 50 artists who follow the president on Twitter, a list made of supporters and critics, to be sure.

On Twitter President Trump has in large part kept quiet about his musical interests, tweeting about singers or events mostly when they intersect with his own business interests. Trace Adkins has been a target two dozen times, mostly about appearances on the NBC reality show Celebrity Apprentice. The same can be said of Rich (of Big & Rich), who also competed on the show.

Luke Bryan made a cameo on the show in 2010, and the president didn't forget when Bryan won the CMA Entertainer of the Year award in 2014:

One year later Brad Paisley would visit with Donald Trump, later revealing that he'd recorded a sketch with Trump that was meant to be a part of the 2015 CMAs, but it was shut down, as by then Trump was digging into his run for president.

On Nov. 24, 2015, Trump would tweet this picture:

Other artists Trump has tweeted about? In January 2013 he called Keith Urban a "solid guy." In August 2012 he tweeted at Taylor Swift, thanking her for a picture and adding that she's "fantastic." On two occasions in 2014 he tweeted quotes he attributed to Johnny Cash. This is a stretch, but over several days in late September 2013 he tweeted several thoughts on Miley Cyrus, saying she's on a slippery path, but calling himself a defender of hers and going as far as to offer relationship advice:

Trump's appreciation for Cyrus is not reciprocated. Leading up the 2016 election she was amongst a vocal group of pop, rock and hip-hop artists that railed against the Republican nominee. On Instagram, she said she'd move if he was elected.

After that it's difficult to find instances where the president has 'gone country.' Noticeably absent from his Twitter feed is any mention of patriot Toby Keith (a 2017 inauguration performer), Natalie Maines (or any of his celebrity critics) or Chris Janson who turned the Tim McGraw song "Truck Yeah" into "Trump Yeah" during the Republican National Convention in 2016. Officially, Janson has never said he supports Trump — those kinds of gigs are known to pay well.

Trump has admitted he's a fan of a few of pop artists, including Billy Joel and the late Michael Jackson. It's not clear how he feels about artists using his name in a song, however. For over four years he tracked the number of YouTube streams of rapper Mac Miller's song "Donald Trump." Early on he would boast that he created a star before wondering where his cut of the profits are, and finally just encouraging him.

"God Bless the U.S.A." was an established hit before Trump used it during the campaign and tweeted about it, but that doesn't mean that should his friendship with Greenwood turn sour, he won't fire back. It's happened before. When asked to quit using Aerosmith's "Dream On," the then-presidential candidate tweeted:

Country Music's Most Political Stars