How Softbank CEO Masayoshi Son turned Sprint into the telecom war's latest casualty

Sprint is about to become the latest casualty of the US telecom wars -- and it's partly thanks to a temperamental, impulsive Japanese billionaire. When Sprint was acquired by Japan-based SoftBank in 2013, it was the nation's No. 3 carrier, boasting cutting-edge tech that included a trove of spectrum that analysts saw as a formidable...