Whether or not Congressmen and Senators (read “McCain”) believe the War Powers Act is constitutional, it is the law of the land until it is either repealed or declared unconstitutional by the Supreme Court, and both Congress and the president must obey it. For that matter, so must the military.
The excursion in Libya was a clear violation of the Act, and Obama should be impeached for it. Whether or not our current involvement is so limited as to fall outside the scope of the War Powers Act, it was not so in the beginning, and was a violation of the Act. A most, failing to get congressional approval within 60 days is a second violation of the Act. The first violation occurred when he committed our armed forces against Libya.
The president and Congress do not get to decide which laws to obey just because they have the personal opinion that the law is unconstitutional (read “McCain”). The military commanders should have refused to obey Obama’s orders to attack Libya because it clearly violated the War Powers Act, and was, therefore, an illegal order.
Now, whether or not the War Powers Act conforms to the Constitution is not for Congress, the president, or the military to decide. It is for the Supreme Court to decide. Whether or not it is a good law, or a good idea IS for Congress to decide, and then the president to sign or veto. But until that is done, it is the law and should be obeyed.
Obviously there are laws which should never be obeyed (e.g., rounding up innocent civilians and putting them in concentration camps), but the War Powers Act is no such law. Whether or not it’s a constitutional law, or a good law, or even a good idea, it is not immoral, and must be obeyed.