The wily genius behind the Softbank-Sprint deal

Not since Japan snapped up the Rockefeller Center in the 1980s has the power of a mighty yen and an acquisitive Japan reverberated so strongly in the United States. This week's $20.1 billion deal between Japan's number three mobile carrier Softbank and the moribund Sprint is Japan's largest outbound investment ever to date, and equally controversial.

The Japanese firm now has a 70% stake in a large chunk of the US tech landscape that, at first, had investors bolting from the scene. But as Softbank's shares rebounded the bold move has convinced some. "We estimate that consolidation could yield $20 billion to $40 billion in direct expense synergies over time," Credit Suisse analysts wrote in a report on the merger. "New capital from Softbank will also allow Sprint to meaningfully improve its spectrum position relative to AT&T and Verizon." The report also points out that Softbank has a strong track record of innovation and cost management. That is something of an understatement. Consider Masayoshi Son, Softbank's chairman. With roots in software sales, he turned Softbank -- a "bank" of software, hence the odd sounding name -- into the undisputed turnaround king of Japanese commerce.