"Not sure that the simple answer here is really the right one. Size & corp responsibility aren't necessarily inversely related."Of course, some large companies can have a highly refined sense of ethics and social responsibility, although this doesn't always protect them from strong disagreements with external lobbyists, as Shell discovered when it wished to decommission the Brent Spar.
In any case, not all large companies can be trusted to regulate their own behaviour in the public interest. Companies pay tax where it suits them, move (or threaten to move) operations from one country to another, shrug off massive fines, and can sometimes behave as if they were above the law, as Fred concedes. In the long term, these legacy corporations may be doomed, but in the short term they can still cause a lot of disruption in the financial ecosystem.
Of course there are no simple answers. I certainly think some companies are too large, and I hope there will always be good opportunities for smaller companies to compete. What I'm calling for is a way of reasoning intelligently about the size of companies, which balances the interests of all stakeholders in a fair and governable manner. I think this is a proper topic for business architecture. And perhaps some of what we've learned from SOA about granularity and governance can be applied to this greater problem domain.