Why the Fukushima radiation leak matters

There have been several articles about the ecological devastation caused from Fukushima's nuclear plant that was damaged in the 2011 Earthquake. Here's an example: http://www.theinertia.com/environment/mother-fukushima/

The gist of these articles is:
1) Hundreds of tons of radiation waste is leaking into the ocean every day since the earthquake.
2) Ocean currents have been transporting that radiation everywhere in the world, most recently to the west coast
3) Many animals species, including some land animals, are dying from unknown causes
4) The seafood we eat has been poisoned.

And each and every of these articles have their doubters arguing:
1) Hundreds of tons of radiation is nothing compared to the vastness of the ocean
2) The radiation content in ocean water, even if increased 10-50x, is still below harmful levels
3) There is no concrete science backing these claims
4) The author is using scare tactics by stringing together random events to get views

First, when it comes human health and the environment, science and the media takes decades to come to conclusions--usually after the damage is done. The majority denied human involvement in global warming until what, 10 years ago? Let's not forget the ecological damage DDT caused that went unnoticed during WWII to the 70's. Or how in the 50's, everyone thought smoking was harmless until people starting getting lung cancer years later. 

Secondly, I don't think the masses realize how sensitive ocean life is. Small fluctuations in ocean acidity, or a temperature increase of just 1C can cause coral bleaching and kill 90% of all life in a region. Maybe 10-30x radiation levels is harmless to humans, but we don't understand how it will affect sea life. 

Thirdly, most of us don't give a rat's ass about ocean life and view this as a localized human-problem that killed a dozen people. Personally, I think this disconnect is due the majority of us never seeing or interacting with underwater life on a routine basis, nor realizing that billions of people rely on seafood as a primary staple in their diet.

So yeah, there's no concrete science indicating the magnitude of the damage caused. It might turn out to be a non-problem. But when it comes to environment or health, I don't think its a risk we can ignore until the data pours in years later.