I didn't see an interpretation. I saw what you wish it meant. The 4th Amendment is clearly stated. Please provide an interpretation.
No. I told you what it means. "Probable cause" is not a standard for surveilling non-American citizens. There is no standard.
And American citizens talking to these up-to-no-good non-citizens have to be surveilled right along with them.
I will ask again: do you believe terrorists have the protection of the Constitution? And, if you say they should, why should they?