Wrong.
The law of the land says that the third of the country purchased by the US from Mexico, shall continue to honor the Spanish land grants, not interfere with any business or commerce, shall not discriminate against any of the residents who choose not to become US citizens, etc.
So actually "open borders" are required by law.
There is no legal way to block access by anyone.
It is also obviously illegal to use troops trained in deadly warfare only, on civilians.
And the right to protest ICE is also protected because ICE clearly is in violation of the law and subject to arrest by anyone and everyone, for not following due process, which requires judicial hearings before any raid, arrest, deportation, etc. And even forced ID checks are totally illegal.