The Boeing airliner now known as MH-370 carries with it more than just 239 passengers and crew, it carries an unparalleled political consequence.

In essence the analysis points to this:
The United States knows by now [Boeing – Aircraft Health Monitoring System – AHMS], and can more-likely prove, by now [Satellite Optical Locating], where the physical location of the flagged Malaysian airliner is. That’s not really the big issue.
The bigger issue shifts, “what now”?
Think about it. If you are a state government, and this plane is physically located in your nation, and your ambassador has been called to an office within the U.S. security apparatus, and you’ve been told (perhaps shown) the evidence that this plane is sitting in your country, what are you going to do ?
It’s not an issue as long as no-one knows where it is.   But once discovered….  No-one, *NO-ONE*, wants to be the nation of location.
Regardless of your nation’s political ideology – the outcome of your nation attached to this plane’s disappearance on day #12 is disconcerting in infinite magnitudes. It matters not whether or not your central governing body had anything to do with it – we’re beyond the point where that would make a difference.
Who would admit –ON DAY TWELVE– that Malaysian Airlines Flight 370 was in their nation ?
NO-ONE. Regardless of global perception no nation wants this toxic political mess associated with them.
Regardless of what the world thinks about you, good or bad, if your nation was a destination for this flight you will face massive (never-before-seen) scrutiny, and potentially embarrassment of unparalleled magnitudes.
AGAIN – based on the reasonable assumption the U.S. intelligence community can identify exactly where this plane is, what would that nation do if faced with the evidence therein ?
Additionally, it would not be in our U.S. best interests to expose/embarrass them. Our strategic goal, and the goal of our strategic partners, would be to make sure this vehicle could not be used as a weapon or for any other illicit purpose.  We could achieve that goal with simple notification that we are aware of where it is.
You can just imagine being a Prime Minister, President, or government representative and being face with the reality that your nation houses such a “hot potato”, and if discovered immediately your regime would have billions of eyes following hundreds of the worlds media as they swarm you with questions like:

•Where are those poor passengers ?
•What happened to their bodies ?
•What do you have to say to their families ?
•How could you “not know” what is going on within your nation ?
•How can you allow this to happen ?
•Is your nation under control ?
•Are there people within your nation that you allow to carry out these things ?
•Are your systems of governance so unstable that such an event is even possible ?
and
•What do you have to say to the mothers, fathers, families of those poor passengers ?

Essentially you’d have two options:

1.) Go out and face an entire world as they tore you, your nation, and your reputation for decades, to shreds.   Knowing this would NEVER be forgotten.

2.) Destroy the evidence. Conceal the event. Bury the story and take action to insure the story/discovery never reaches the light of day.

I can’t think of a nation capable of doing #1  – Not even our own.
If #2 – you might also choose to take the “black boxes” (after cleaning up the data) to a distant location (Southern Indian Ocean / Australia) and then conveniently have someone (fisherman or tipped search party) discover them a long way from you allowing the world to reconcile the plane came down in some distant location – under some undetermined circumstance.
….Then deal with the internals – quietly.