Build the wall, keep the army.
I am supervised that you bought off on the Posse Comitatus lie. It was a law preventing the Army from enforcing laws on US citizens not from apprehending foreign nationals. Don't be an idiot and fall for that lie.
The US Army exists to defend the US from foreign invasion, which is expressly authorized by the US Constitution. Guarding the Mexican border was the Army’s primary peacetime mission until 1940, and no one ever declared this was in violation of this 1878 act. The US Border Patrol wasn’t even formed until 1924, so claiming the intent of this law was to prevent US Army troops from guarding the border is absurd. The map at left shows US Army forts in Texas in the late 1880s when the entire US Army had fewer than 40,000 soldiers; it has 500,000 today. Clearly, defending the US border was a primary mission of the US Army for decades after this act was passed.
Read more at: The Posse Comitatus Act does not prohibit US Military on our borders.