Immigration has a been a ‘mess’ for a while. While “ We wouldn’t have the illegal immigration issue had Obama enforced our immigration laws.” has some merit, it is also the case that the Obama administration expelled a goodly number of dangerous illegal immigrants, leading to an estimated reduction in the number of illegals during his term. Heck, listen to Bush and Reagan face off on the topic.. https://youtu.be/Ixi9_cciy8w in 1980
Also, at least one state which had been successful at dissuading illegals from spending time there have had sufficient problems getting crops picked, etc, that they ended up backing off.
So… Trump ‘inherited’ a mess, as did Obama, which was made worse under Bush Jr. before him. And for which no meaningful fix was offered by the Republican majority congress over the past 6 years (who continues to seem to be content to let businesses use illegal immigrants to keep costs down). Hopefully he will at least do better than Bush Jr, and with luck better than Obama. It’s hard to me to feel to sorry for him on this topic, it’s not like he wasn’t aware of it when he was running.