Sorry GJC, the lefties prefer to live in their self judging bubble of supposed peace and harmony (lots of that provided everyone else conforms to their self reinforcing group thinking). In their world it is utopia to let in the unwanted uneducated illegal invaders because their will adjust and become productive / contributing citizens.
I note some do get somewhat violent when people don't conform to their group think.
In the real world - the illegals become long term unproductive welfare leeches. In the end, yes - you are right - the left are being used like useful idiots. They are too dopey to realise that - because of their idealistic unrealistic shortcomings.