There is no humor in this statement. EVERYONE needs to immediately contact their Congressional reps (democrat or Republican) and demand a clarification of THIS threat against the people of this nation, made by a sitting US President.
This can only be taken only three ways
1). He is insane, making him a danger to the security of the US and
Immediately removed from office.
2). He has all his mental faculties, and meant every word he said, and
would not hesitate to bomb citizens of the US, which means he is
an enemy of the people, a clear and present danger and needs to be
Immediately removed from office.
3). Or he is both of the above and needs to be immediately removed from
Office.
Impeach!