If a wall is such a dumb ineffective idea why don’t Democrats just support it since it will continue to allow people to come in illegally?
You seem to be suggesting that it is the objective of Democrats to continue to allow people to enter the country illegally. Do you truly believe that?
The wall being ineffective is a good argument against it, but it isn't the only one. Even an ineffective wall will surely damage the relationship between the two countries it separates, for example.
I do believe Democrats want people to enter illegally, instead of not at all. Based on things they say I see no reason why to think that’s not the case.