When you take into account that Fukushima was the result of industrial sabotage and deliberate destruction by Israel (rightly or wrongly to prevent sale of enriched uranium to Iran) then the risk of nuclear meltdown in America is minimal unless it is also carried out deliberately.

There are too many redundant safety systems in those nuclear plants to allow for the possibility that each system component (of which there are hundreds) failed simultaneously when the individual failure rate is stupidly small.

Also, the earthquake magnitude and tsunami magnitude are not reconcilable. The earthquake was around 6.8 mag whilst the tsunami was on the scale of a 9ish mag quake. Best theory is subsea detonation of a nuclear device causing a simulated earthquake and massive tsunami. Evidence does not support a 9mag earthquake prior to tsunami. Investigation of post-quake damage clears that one up straight away (as in, there is not sufficient damage to support a 9mag quake report).

If a nuclear reactor is targeted in America, it will meltdown, but left to normal operation, there is negligible risk of a Fukushima-style meltdown.