You can read what the FBI is tracking in this category here. This is report on Domestic Terrorism and it talks about Domestic Violent Extremists. DVEs they call them.

https://www.dhs.gov/sites/default/files/2023-07/23_0724_opa_strategic-intelligence-assessment-data-domestic-terrorism.pdf

They have several categories under Anti-Government or Anti-Authority Violent Extremism including Militia Violent Extremism and Anarchist Violent Extremism.

This is the new category, the guy is discussing in Newsweek.

Anti-Government or Anti-Authority Extremism-Other

This is what the report says

AGAAVEs citing anti-government or anti-authority motivations for violence or criminal activity not otherwise defined include, but are not limited to, those motivated by a desire to commit violence against individuals or entities they perceive to be associated with a specific political party or faction thereof. AGAAVE-Others do not fit within the AVE, MVE, or SCVE threat subcategories.Threats from these DVEs have increased in the last two years, and any further increases in threats likely will correspond to potential flashpoints, such as high-profile elections and campaigns or contentious current events.

Historically, these DVEs have conducted or plotted attacks targeting perceived political opponents, including elected officials, other government officials and law enforcement, candidates for public office, political party offices, and members of the media. In 2018, a DVE mailed 16 IEDs packed with explosive material and glass shards to victims including prominent figures in the media and Democratic Party; he pleaded guilty to 65 felony counts and was sentenced to 20 years in federal prison. In 2017, a now-deceased DVE injured several Republican members of Congress, staffers, and responding officers after opening fire at a charity baseball event in Alexandria, Virginia.

More recently, an AGAAVE-Other subject was indicted in November 2022 on charges related to breaking into the residence of the then-Speaker of the House and assaulting the Speaker’s husband. Since FY 2022, at least six other AGAAVE Other subjects were arrested for threatening government or law enforcement officials to whom they were ideologically opposed. These DVEs likely will continue to pose a heightened threat as they plot or threaten violence to redress political and/or social grievances and continue to draw inspiration from conspiracy theories surrounding a range of current events. Investigations, arrests, and prosecutions related to the 6 January 2021 breach of the US Capitol are ongoing, and dozens of these subjects are categorized as AGAAVE-Other. For example, in March 2022, an AGAAVE-Other subject was arrested in Miami, Florida, for alleged activity related to the Capitol breach; in June 2022, he and four associates were charged in a superseding indictment with seditious conspiracy and other counts.

I may not like Pelosi, but I'm not going to attack her husband with a hammer.