The first amendment:
"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."
Let's look at that last clause. Is not a public sector workers' union the enactment of people peaceably assembling to petition the Government for redress of grievances?
Is this clause not as binding as the religion, speech and press clauses?
Does the executive branch have a responsibility to enforce the constitution?