And given how big the market share of Nordea is in Sweden (and other Nordic countries, for that matter) that would probably bring down the Swedish, and possibly Nordic economy. Which would then impact a lot of the EU as well, I guess.
Ever since reading this article I've wondered if these COBOL programmers that keep banks like this running are an enormously underestimated "bus factor" for many of the world's economies, and what kind of back-up plans they have for such a scenario.