I think Bidan's plan is too push Americans into open revolt, then call in the UN.
The border crossers will be then fitted into UN Kit.
The UN called in is a result of the US populace not accepting the authority of the US military due to credibility and competence issues. Destroying the public acceptance/willingness to allow the US military to attempt to restore public order is the job of Milley and McKenzie.
The above may not be true at all, however the real problem is it would be pretty hard to disprove by careful observation of the Bidan boy's moves and of the actions of Miley & McKenzie so far. Everybody's good at something, they say.
Milley could very well warn the UN troops of any impending proud boy/white supremacist raids and Mckenzie could be on the tube 24/7 dishing out, "My bads" for all the towns under his watch the UN destroyed in the process of saving them.
Who the fuck knows anymore?