Because the President doesn’t “adjourn” and leave town like congress has done during this shut-down. The President can’t approve or veto legislation until passed by the Congress.

If the President does leave town, he leaves on Air Force 1 that has a full communications suite. If Congresses pass legislation then that legislation can be transmitted to AF1, printed and signed by the President in seconds. Congress on the other hand must have a quorum present to conduct business and be physically located in the Capital Building to pass legislation.

(On the other hand I have no qualms about locking the President in the Oval Office, give him/her a sleeping back and feeding him/her MRE’s until Congress passes legislation.)

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