Interesting. I think it might be a matter of what "leftists" you hang around with/are exposed to, and just possibly how much time you spend on Twitter (a personal bugbear of mine).
Most of my friends consider themselves pretty far on the left, and I don't think any of us have the attitudes about immigration that you're discussing. I think in general our appraisal of the situation is, "It's way more complicated than you think." Reductionist solutions like "Build a wall" or "Remove all borders" are, well, just dumb.
When we talk about the flood of immigrants to our borders, the question frequently turns to root causes. Looking at immigration from Latin America specifically, we have a long history of exploitation and extraction of wealth and resources from those countries. Just like we built our country of slavery, we have done (and are continuing to do) similar levels of exploitation below our southern borders. So when you think of things from that point of view, the range of possible solutions does not usually include "remove our borders" (seriously I've never heard anybody advocate that. If you have, I wonder if it was on Twitter?). It's more like, "corporations who do this kind of thing ought to be heavily taxed, or else prove that they are improving the lives of people in their home countries", etc.
So, as a sort of tl;dr - the leftists I know don't advocate massively increased immigration. We are in favor of treating people humanely, and increasing regulation and taxation on corporations that benefit from keeping places unstable and generally undesirable places to live.
Most of my friends consider themselves pretty far on the left, and I don't think any of us have the attitudes about immigration that you're discussing. I think in general our appraisal of the situation is, "It's way more complicated than you think." Reductionist solutions like "Build a wall" or "Remove all borders" are, well, just dumb.
When we talk about the flood of immigrants to our borders, the question frequently turns to root causes. Looking at immigration from Latin America specifically, we have a long history of exploitation and extraction of wealth and resources from those countries. Just like we built our country of slavery, we have done (and are continuing to do) similar levels of exploitation below our southern borders. So when you think of things from that point of view, the range of possible solutions does not usually include "remove our borders" (seriously I've never heard anybody advocate that. If you have, I wonder if it was on Twitter?). It's more like, "corporations who do this kind of thing ought to be heavily taxed, or else prove that they are improving the lives of people in their home countries", etc.
So, as a sort of tl;dr - the leftists I know don't advocate massively increased immigration. We are in favor of treating people humanely, and increasing regulation and taxation on corporations that benefit from keeping places unstable and generally undesirable places to live.