The General Staff of the Armed Forces of Iran, the highest-ranking branch of the nation’s military, issued a statement vowing to “spare no effort” in fighting the U.S. military on Tuesday, suggesting the potential of a planned attack against Washington.

Like other branches of the Iranian government and military, the General Staff referred to U.S. Central Command (CENTCOM) as a “terrorist” group, a response to the declaration by the U.S. State Department on Monday that Iran’s Islamic Revolutionary Guard Corps (IRGC) would join the agency’s list of Foreign Terrorist Organizations (FTOs) for its decades of involvement in terrorist activity worldwide. The Iranian Islamic regime rapidly responded to the declaration – the first of its kind against a state actor – by reciprocally branding the U.S. military a terrorist group.

“The General Staff will spare no effort in supporting the IRGC’s counter-terrorism measures in fighting the terrorist CENTCOM,” a statement from the agency read, according to Iran’s state-run Press TV outlet. “A review of criminal and bloodthirsty America’s adventuristic actions in the region over the past several decades proves the fact that Washington wastes no effort towards destabilizing the West Asia region as a means of creating a comfort zone for the infanticidal Zionist regime [of Israel].”

The statement did not elaborate on how the Israeli government is “infanticidal,” though the accusation has become a recurring one in anti-semitic circles. It also did not specify what it meant by “fighting” – whether the IRGC would deploy in areas where the U.S. military operates and attack its locations.

The IRGC – which has extensive ties to the Shiite terrorist group Hezbollah and is believed to have operated on behalf of dictator Bashar al-Assad in Syria – has boasted of attacking and killing American soldiers in the past.

“America has suffered more losses from us than we have suffered losses from them,” Brig. Gen. Esmail Qaani, the deputy commander of the IRGC’s Quds Force, said in 2017.

Similarly to Iran’s Supreme Leader Ayatollah Ali Khamenei and President Hassan Rouhani, the General Staff also repeated on Tuesday the unsubstantiated claim that the United States created the Sunni Islamic State terrorist group, which Iran, as the world’s largest Shiite-majority country, opposes.

The military claimed to oppose Washington’s “support for terror groups, such as Daesh, al-Qaeda, and al-Nusra [Front], in whose creation and evolution it has, itself, played a central role.”

Labeling the U.S. military a “terrorist organization” was among the first moves the Iranian government made in response to the State Department’s FTO branding, a bizarre move given that the Iranian government does not typically keep a public list of terrorist groups the way the State Department does. Iranian lawmakers approved the move, opening a new session on Tuesday chanting “death to America” and wearing IRGC uniforms in solidarity.

Rouhani and Khamanei both responded to the declaration with belligerent remarks.

“You made another mistake and called the IRGC terrorist; nobody cares what you do,” Rouhani said on Tuesday. “Today, the global arrogance and the United States are venting their animosity and [making up for their ] defeats by calling terrorist a group whose main motto has been fighting terrorism.”

Speaking again n Wednesday, Rouhani called the designation a “foolish and unwise measure” and praised the IRGC as a “defender of freedom” in the Middle East.

Khamenei did not directly threaten the United States, instead warning that the move would “boomerang” on America without specifying how and dismissing the officials who made the decision of blacklisting the IRGC as “idiots.”

“With their deceit rebounding back to themselves, the Islamic Republic’s enemies — such as Trump and the idiots … in the US government — are moving toward rock bottom,” Khamenei remarked.

The IRGC was among the last of the Iranian institutions to comment on the news. On Wednesday, the head of the organization, Major General Mohammad Ali Jafari, called the designation “laughable.”

“We powerfully announce, and we are even ready to provide this information to them, that in the next year, the IRGC will be more powerful than before in its defensive and offensive systems with the grace of God,” Jafari declared. “This action by the Americans is very laughable because the IRGC is in the hearts of the (Iranian) people and our credibility has not been gained from Americans but from the dear and honest people of Iran.”

“The IRGC and the Army will stand together and support the deprived and the oppressed everywhere in the world, and have no fear,” he concluded.

The IRGC and its proxies like Hezbollah are believed to be responsible for dozens of terrorist attacks around the world since the 1979 Islamic Revolution, most notably the 1994 bombing of the Argentine-Israeli Mutual Association (AMIA) in Buenos Aires, the deadliest terrorist attack in the Western Hemisphere before September 11, 2001. Secretary of State Mike Pompeo recalled this history in his remarks Monday, explaining that the unprecedented measure of blacklisting a state entity was necessary “because the Iranian government’s use of terrorism as a tool of statecraft makes it fundamentally different from any other government.”

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