Secretary of State John Kerry on Sunday blasted Russian President Vladimir Putin’s “stunning, willful” choice to invade Ukrainian territory and warned of possible sanctions. “You just don’t in the 21st century behave in 19th century fashion by invading another country,” Kerry said on CBS’s “Face the Nation,” one of several appearances on network interview shows. “It’s serious in terms of the modern manner in which countries resolve problems,” Kerry said. “That’s not the act of somebody who’s strong, “ Kerry added, saying Putin is acting out of “weakness” and “desperation.” On ABC’s “This Week,” Kerry called Putin’s move a “brazen...