Article 2 (The Executive Branch), Section 1 (The President) of the Constitution of the United States of America states :
Before he enter on the Execution of his Office, he shall take the following Oath or Affirmation:
“I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States.”
Back to the Constitution, Amendment 1 (Freedom of Religion, Press, Expression):
“Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.”
So, riddle me this Batman: How, with his constant attack on the free and independent press, is the President upholding and defending the Constitution? How does his threat to revoke press credentials fit into the oath he swore? The long and short, is a failure to adhere to a sworn oath of office an impeachable offense?