In my opinion.... putting policies in place to deter illegal immigrants from coming should be the first, immediate step. Four policies should be:
1) Anyone who crosses the border illegally is permanently banned from being considered for future U.S. legal residency. See some exceptions in point 2.
2) Everyone who crosses the border illegally will be deported to their country of origin within three months. Increase the number of judges determining these cases. Exceptions will be made if the person was in the U.S. previously or if they have family in the U.S. that must accept financial & legal responsibility for them. Also there should be medical care exceptions granted for periods of time for those crossing the border seeking urgent medical attention in a hospital that is not related to pregnancy.
3) Anyone claiming refugee status must apply at the U.S. Consulate in their home country outside the U.S. -- not at the border. Greatly increase the number of refugees allowed from the three central American nations to accommodate this surge. Grant priority to women, children, and families.
4) Mandatory 20 year prison terms for coyotes caught smuggling people across the border. The human trafficking must stop.
How do you make it illegal for people arriving at the border to seek asylum?