Except travelers are not "on us soil" until granted entry by customs. Customs could just deny entry if foreign travelers won't voluntarily consent to search.
They even had 2 canine units circle my car and jump in and out of it at least 10 times each.
Talk about a heavy handed approach.
As long as you know you're not actually carrying contraband or is a terrorist, just smile, comply when reasonable, and then say politely that you'd like to see their manager to file a complaint.
And I have Canadian citizenship.
Signed and donated. It happens to me every, single, fucking, time, losing 1 hour every trip back home.
Since August 15, US border agents in Canada are now able to prevent you from withdrawing if they detain you. (Bill C-23)