Seawalls are a bandaid fix, yes, but they're probably a reality we'll have to deal with at this point. We may have passed the point of inevitability for this rise in sea level -- barring, as the article suggests, any unforeseen stabilizing or countervailing forces to balance out the loss of the ice sheets.

Basically: seawalls aren't the solution, but they're probably part of how we cope with whatever degree of sea-level rise is already bound to happen at this point.