Is 'I Didn't Know' an Okay Excuse for a President?

At what point is "I didn't know" no longer an acceptable excuse for a sitting president?

Is 'I Didn't Know' an Okay Excuse for a President?
The White House

It's become a familiar refrain from the Obama administration. 

“I can assure you I certainly did not know anything.” ​(Via NBC)

He didn’t know the Justice Department was targeting journalists over leaks. (Via Fox News)

REPORTER: “When did the President find out ...?”

CARNEY:  “Yesterday." (Via The White House)

He didn’t know the IRS had been targeting conservative groups. (Via ABC)

REPORTER: “So what day did you learn?”

CARNEY: “The same day the President did.”

REPORTER: “From news reports?”

CARNEY: “Correct.” (Via The White House)

He didn’t know about the problems with the healthcare website before the rest of us. (Via CBS)

CARNEY: “We did not know until the problems manifested themselves after the launch that they would be as significant as they turned out to be.” ​(Via C-SPAN

And in the case of the alleged NSA snooping on Angela Merkel’s cell phone, it’s still unclear exactly what he knew and when. (Via BBC

But at what point is ‘I didn't know’ no longer an acceptable excuse for a sitting president? (Via The White House

The Washington Post’s Scott Wilson says the line is wearing thin.  

"Especially  the way Obama has cast himself over the course of his presidency as a very competent manager, that details matter ...  Each one raises the question of when does he want information?”

But even Ari Fleischer, George W. Bush’s former White House press secretary, says it’s impossible for the president to sign off on all matters. He told Politico“There are certainly legitimate reasons why the president wouldn’t know about something. It might not rise to the level of being in the [Presidential Daily Briefing]." 

And while some say the president’s recent problems were beyond his control, it does beg the question — who is in control? 

“What he doesn’t seem to want to have is a chief executive strategy and a chief executive structure. Every time something gets screwed up out there there’s a sense he might not actually be involved. I don’t think that’s the way it ought to be.” (Via MSNBC)

Analysts say the recent disclosures have put the president’s credibility at risk. National Journal's Charlie Cook writes: “What makes these problems more troublesome than some other controversies is that they go to the question of Obama's competence, rather than to differences of policy or ideology.”

That perception looks to be growing. A Gallup poll released Tuesday found the president’s approval numbers have dropped to an all time low — with just 39 percent of Americans approving of his job in the White House.

But perhaps the blame best lies with the people around the president who left their boss in the dark. Here’s Mack McLarty, former chief of staff to Bill Clinton, told CNN:

“I do think cabinet officers and White House officials are expected to take and assume full responsibility ...  and to take some heat. But I think ultimately Harry Truman had it right — the buck stops in the Oval Office.”

 ... A president who also famously once said: 

“A president either is constantly on top of events or, if he hesitates, events will soon be on top of him. I never felt that I could let up for a single moment.” (Via Department of Energy)