Some of you addicts to the lame stream media seem to be indoctrinated to believe that the US president controls border security.
This is false - fake news.
Congress authorized it, Congress makes the rules, Congress oversees whether those rules are being followed and has the power to change the rules if needed.
DHS and CBP are authorized to exist by Congress and obligated to the parameters laid out by Congress.
Impeachment of DHS secretaries changes nothing. Congress has the power to reform US border security and chooses not to do anything about it.
The president's hands are tied by Congress, particularly the house of representatives who refuse to discuss a border protection bill already passed in the Senate.