When he wasn't tightening the border to try to get immigration reform passed, Obama used it as an alibi, i.e. not as wall but as an excuse to deport those whose unauthorized crossing would not be tolerated.
#toleratedillegality in border crossings is just one of many cases where the balance of forces & the state conspire to have the law serve mostly symbolic purposes. While Obama did the right thing to try to create a path to citizenship for MILLIONS,
even his approach externalized the costs of our own drug war by deporting those caught up in it & refused the costs of the way we fought the Cold War that destabilized societies people try to escape.
At present, it seems almost impossible that Americans will achieve a Smithean impartial spectatorship on our own society and act in accordance with global justice. For such a view of ethics, see Amartya Sen's Idea of Justice for which there seems to be no real audience presently
