As for the courts, if there is any precedent to go by, when the family of assassinated Anwar al-Awlaki tried to sue the government over his targeted killing in Yemen in Yemen in 2011, the court said they didn't have standing and it was dropped.
As for the targeted killing of Awlaki's son two weeks later in another drone strike, his killing has seemingly gone off the radar, even though he was aged 16 at the time, an American citizen and had done nothing wrong; apparently just a case of guilt by association i.e. he's Awlaki's son, just terminate him as well.
For some of us, the idea of the Constitution being shredded is not something new. It was clearly evident during the George W. Bush presidency with the legally dubious memos written by then Justice Department flak John Yoo justifying the torture (enhanced interrogation techniques) of detainees. Again these memos were always kept secret for reasons of national security and only became known when they were leaked to the press.
These secret, legally dubious Justice Department memos are of course still being written by the current administration. For all practical purposes they've become the "new" constitution and the law has become whatever they say it is.
[1] "U.S mulls strike on American, officials weigh new kill-list rules, citizenship of suspect in Pakistan", by Ken Dilanian, "Tribune Washington Bureau" for "The Baltimore Sun", February 11, 2014.
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