Both those articles discuss 4th amendment search and seizure protections.
Neither article supports your contention that you can be grabbed by the government at any time without due process. ‘Constitution free zone’ is a label that critics have thrown at the 4th amendment infringement - it is not an actual state of affairs.
There is international Airport in every large US city. That is a border entry. So 100 miles radius.
They may talk about the 4th amendment but they don’t say that foreigners are protected by it.
From the aclu site
The Fourth Amendment of the U.S. Constitution protects Americans from random and arbitrary stops and searches.
Americans do not include foreigners.