The amount of private data about individuals that JP Morgan has makes it a very attractive target to attackers despite any difficulty (perceived or real) it takes to get the data.

Extending that logic, it means the NSA is an even more worthwhile target for attackers, because they have far more private financial data about individuals in the USA and people abroad. But you can bet that when (not if) a breach of the NSA happens, it will never be reported to the public.

The only solution here is to do away with these centralized stores of all our private and financial information, so the incentive for these attacks no longer exist. There's no amount of technological hardening that will prevent a determined attacker (state sponsored or otherwise) to give up, when the reward for a successful attack is so high. Until then, reports of massive data breaches are going to be more and more common.