It is not appropriate to limit our understanding of this trouble as "the subprime mortgage problem" or interpret it as "the financial sector's fault". In essence, it was caused by the bursting of a global credit bubble – a phenomenon generated by a combination of the rise in asset prices and the increase in credit and leverage.
During the period of the credit bubble, firms in general enjoyed the fruits of high growth in the world economy. The rise and bursting of the credit bubble was observed to the greatest degree in the U.S. economy, but other economies also experienced similar phenomena, albeit with some differences in degree.