Comment: Both Afghanistan and Iraq

Both Afghanistan and Iraq were authorized by Congress.

S.J. Res. 23
H.J. Res. 114

If this is not authorization, then goodness, what is it?

And note, the Constitution doesn't specify a specific "format" for how Congress is to "authorize" or "declare" a war. That is open to interpretation, this is what lawyers fight over. You may disagree with how they worded it, but Congress did clearly provide authorization. Bush did not act unilaterally.

Obama has unquestionably encroached on this Constitutional authority, that happened long ago starting with Lincoln. But to say the Constitution is totally dead is poppycock. If you actually believed that then you're a hypocrite for not doing anything about it.