I'm for bias and bigotry ...
We know. Just don't call it racist, even though it is just as bad ... kind of the litmus test for bias and bigotry in the US these days.
But that's your "shared cultural values" ...
if it means excluding criminals, ...
Anyone with a criminal record gets deported, unless they can show they qualify for amnesty.
... jihadists ...
Who always identify themselves at the border ... isolating them is no different than isolating "home grown" terrorists and hate group members.
... and leftists ...
That's you with your bias and bigotry again, laughable this one, and again there are "home grown" Americans that are leftist (which is no crime last time I looked ... it's just political leaning, the kind of politics that brought you 8 hour days, weekends and vacations ...).
... communists ...
Again, politics, and lots of Americans are members already ... home grown ... and it too is not a crime ...
... and people who poop on sidewalks.
Now you're just being facetious ...
The point I would make is that if there are immigrants that are essentially no different than current Americans, by what "standard" are they to be excluded?
Enjoy