The widely accepted view is that the federal government is allowing "military-aged men" of Islamic and Chinese origin to cross the border. The marxist elites are building an insurgency. This is not a fringe view, it's common.

What kicked off this specific thing was that Texas put blades and razor wire along the border. The feds came in and took it down because you can't maim people from other countries, even if they're crossing your border illegally. Texas didn't like that and so they're making it an issue to show they're standing up to the feds and their borderless agenda.