It seems like there are many reasons why this won't work. Why are they trying to beat this thing thermally? It seems unsustainable at the outset, in terms of cost and maintenance, let alone whether it will work in terms of mechanics and chemistry. If it's such a grand scheme that it's projected two years out, maybe the assumption should be that it's too complicated for Tepco to handle and/or it's too complicated for the delicate situation on the ground at Fukushima (where what integrity exists seem to be falling apart quickly).
And though it seems like Tepco and Japan have been a bit incompetent in handling things like disclosure, responsibility, approach, and honesty, it probably will never happen that Japan will be elbowed out of the way by any outside agency, including the UN. Japan still has Tepco on the ground at Fukushima because it's Tepco's problem and potentially Tepco's fault. It's much easier to keep the blame-monster fully enclosed in one cheap and effective enclosure than to spread its infection to numerous other parties. If Tepco fails, Japan can blame them because nobody else has had a hand in it. If Tepco moves out of the way and lets the Japanese government handle it, then Tepco can be dispatched for being incompetent, and potentially all of their resources and assets can be liquidated toward the effort. Having a third party involved make it a potentially stickier situation with less decisive consequences and less narrow goals and demands to be met.
You can take that relationship and expand on it to see why it is almost a bad idea to step in from outside of Japan. If radioactive plumes reach California and nobody has been involved but Japan and Tepco, then who can be blamed? Only Japan and only Tepco. If it has become an international effort involving Russians ... no, bad idea ... involving some engineers from somewhere (?) then that at worst leaves us with even more parties to blame and, potentially, even more duplicity along the way while at best it leaves us with a sort of muddied water where feel-good "we're all in this together" has completely erased the instinct to place blame. Without the prospect of blame and consequences, you get foot-dragging and indecisiveness which all the bleeding hearts in the world won't drag out of lethargy.
You can say that the real-world, radio and chemical consequences should be enough to push us all to shove those competitive instincts out of the way but I personally don't think that will ever happen.
As some have pointed out, Fukushima isn't even a talking point. Grand standing and chest-beating over an obviously snafu situation where major news reporting more closely resembles yellow journalism than actual information and where the politically accused party is being accused by those with vested interests in that party's failure who've made this accusation and failed before, is the call of the day.
I'm sure the level of sardonic "irony" so prevalent in global culture today is enough that most people can understand why Japan will be left to figure this out on their own until they ask for help, and why at which point any countries expected to help will have to be dragged out of bed kicking and screaming by citizens "blowing whistles" about irradiation before any semblance of effort is really shown.
