How has the Constitution made the Supreme Court Independent?

-Life Tenure, no Retirement Age. Only 1 SCOTUS Justice was Subject to Impeachment Charges, that was in 1805 -Salary which will not be Intervened. Roughly $270K -Justices are Appointed, not Elected. Presidents Nominate, Senate confirms. This Helps to not allow a Single Part Dominate -SCOTUS has own Powers within Constitution ensuring its Sovereignty. A President, who Disagrees with the Ruling, can not really Change it