As for the Fourth Amendment, Courts have consistently established that there is a foreign intelligence exception to the warrant requirement of the Fourth Amendment. The Terrorist Surveillance Program falls under that exception.
Here's what the FISA Court said in 2002 in the case of In Re: Sealed Case, 310 F.2d 717, 742.
The Troung Court, as did all other courts to have decided the issue, held that the President did have inherent authority to conduct warrantless searches to obtain foreign itelligence information... we take for granted that the President does have that authority
Agreed about disagreeing.
9-11 was surely an act of war but Congress did not respond with a genuine declaration of war. That would have entailed “declaring war” on the Taliban, or Al Queda, or Afghanistan. And the end (that is, the objective) of that war would be clearly defined if not necessarily forecast - the destruction or surrender of the named enemies. But who is Terror? Where does he live? How do you defeat him? How do you know when you have defeated him? Who knows? So now the government uses this “war” to claim vast new powers not granted to it by the Constitution, but because the “war” is undefined and therefore unwinnable the government will likely exercise those ill-begoten powers in perpetuity.
Regarding Amendment IV, one big philosophical divide here - correct me if you disagree - is that you more or less accept the “living Constitution” argument famously stated by Chief Justice Hughes in these terms: “the Constitution is what the judges say it is.” Otherwise, why point to court decisions that have no independent textural basis in the Constitution, indeed, that directly contradict the language therein? I, however, believe that the Constitution is what IT says it is.
Someone in an earlier post mentioned “historical perspective” - one of the dominant themes of 20th century American political history has been the federal invasion of individual liberties and the obliteration of the separation of powers as aided, abetted, and often spearheaded by the judiciary.
The decisions you cite may well make warrantless searches “legal;” they cannot make them “constitutional” because the courts lack legitimate authority to in effect amend the Constitution by fiat - or as someone else here said earlier, to “make it up as they go along.” But they do it anyway.
Welcome to post-constitutional America. Sucks to be us...