President Donald Trump launched a scathing attack against Rep. Thomas Massie on Sunday, June 22, calling the Kentucky Republican “weak,” “ineffective,” and a “simple minded ‘grandstander'” following the congressman’s criticism of U.S. strikes on Iranian nuclear facilities.

The public feud escalated after Massie condemned Trump’s decision Saturday, June 21, to authorize strikes on three Iranian nuclear facilities, writing on social media that the action was “not Constitutional.” The Kentucky congressman argued that the Constitution does not permit the executive branch to unilaterally commit an act of war against a sovereign nation that has not attacked the United States.

Trump responded with a lengthy post on Truth Social, declaring Massie “not MAGA” and claiming he votes “NO” on virtually everything put before him. The President compared Massie to Sen. Rand Paul, another Kentucky Republican known for his libertarian positions. Trump indicated that “we will have a wonderful American Patriot running against him in the Republican Primary, and I’ll be out in Kentucky campaigning really hard.”

Two key Trump advisers, Chris LaCivita and Tony Fabrizio, confirmed Sunday they are launching an anti-Massie super PAC aimed at unseating the congressman in his next primary election. LaCivita, a senior political adviser to Trump, confirmed the formation of the group to NBC News.

The conflict represents the latest chapter in a long-running dispute between Trump and Massie, who has represented Kentucky’s 4th Congressional District since 2012. Trump previously wanted Massie thrown out of the GOP in 2020, though the congressman retained his seat and even received Trump’s endorsement in 2022.

Massie has consistently opposed Trump’s legislative priorities during his second term, including repeatedly voting against what Trump calls his “big, beautiful bill” throughout the congressional process. Last week, Massie partnered with Rep. Ro Khanna, a California Democrat, to introduce a war powers resolution designed to prohibit U.S. involvement in Iran.

Following the Iranian strikes, Massie defended his position by posting a fundraising appeal and appearing on CBS’ “Face the Nation” Sunday, where he advocated against American involvement in a war with Iran. He later wrote on social media that Trump “declared so much War on me today it should require an Act of Congress.”

The congressman also criticized Trump’s Sunday afternoon post on Truth Social that asked “why wouldn’t there be regime change” in Iran and called for making “IRAN GREAT AGAIN.” Massie responded that such rhetoric was “not America First folks.”

Trump’s regime change comments appeared to contradict statements from his own administration officials. Defense Secretary Pete Hegseth emphasized Sunday morning that “this mission was not and has not been about regime change,” describing the operation as a precision strike to neutralize threats from Iran’s nuclear program. Vice President J.D. Vance similarly stated on NBC that the administration’s view has been clear about not wanting regime change.

Secretary of State Marco Rubio reinforced this message on Fox News Sunday, stating that while he dislikes the Iranian regime, the United States is “not into the regime change business here.” Rubio emphasized that the administration focuses on American safety and security rather than toppling foreign governments.

Currently, only one Republican candidate has filed to challenge Massie in the primary for Kentucky’s 4th District. Niki Lee Ethington, a registered nurse who graduated in 2021 and has not held public office, represents the sole declared challenger according to her campaign website.

Trump has previously demonstrated success in targeting Republicans who opposed him, particularly during the 2022 election cycle when his political operation focused on GOP lawmakers who voted to impeach him after the January 6, 2021, Capitol assault. Eight of the 10 House Republicans who voted for impeachment either lost their primaries or chose not to seek re-election.

The current dispute occurs against the backdrop of escalating tensions in the Middle East, with Iran retaliating for the U.S. strikes.