"It's a very difficult balancing act to get right," said Wit, a visiting fellow at the U.S.-Korea Institute in Washington who runs the "38 North" website that reports on North Korea developments. "I think we're verging on too strong a response."
Obama has been "regularly updated" on the crisis, White House spokesman Jay Carney said Thursday.
"We are obviously consulting regularly with our allies in Seoul and Tokyo, as well as other allies and partners," Carney told reporters as the president returned from a two-day trip to California.
State Department spokeswoman Victoria Nuland said that there's an opportunity for Kim's regime to de-escalate.
"We have also been saying all the way through that this does not need to get hotter," she told reporters Thursday. "We can change course here if" North Korea halts its nuclear and missile tests as required by its international obligations.
For now, Kim doesn't seem to be moving that way. South Korea Defense Minister Kim Kwan-jin told reporters in Seoul Thursday that North Korea may be preparing a medium-range Musudan ballistic missile — which may be capable of reaching Japan — for a test launch.
A test may be timed to mark April 15, when North Korea commemorates the birthday of Kim Il Sung, the current leader's grandfather and the nation's founder. A year ago, North Korea used the April 15 parade to display for the first time what U.S. intelligence agencies said "appears" to be a new long-range road-mobile intercontinental ballistic missile.
"They are setting up for their end game — a missile test and then the propaganda narrative that they have caused the U.S. to back down because of the North's superior military capabilities and that it's a nuclear power," David Maxwell, associate director of the Center for Security Studies at Georgetown University in Washington, said in an email.