North and South Korea, which have technically been at war for the last 65 years, are again acting like it.North Korean troops are on high alert after the North fired a rocket across the demilitarized zone separating the two countries this week.The South has responded with dozens of shells.Steven Borowiec reports for The Los Angeles Times, and joins me now from Seoul, South Korea.Welcome to the program.Thank you for having me on.So I understand what sort of kicked this off is that South Korea began kind of blasting anti-North propaganda out of loudspeakers on the border, which is something they used to do in the past.What's going on?Well, it all kind of comes from explosion in the DMZ, which is the sort of de facto border that separates North and South Korea, which injured two South Korean soldiersthat the South has blamed on North Korea but, of course, North Korea has not apologized for.That recently led to a spike in tensions and then the South Korean government decided to restart these propaganda broadcasts, which they normally don't do.And things have just kind of escalated from there.Can you talk about what indications people see that the North is mobilizing in any way, in terms of short range missiles and other things?Well, most of that comes from the South's intelligence agencies.You know, they monitor very closely North Korean military as they move throughout the country, as they mobilize different kinds of forces that are normally not in action.I think something that's unusual about the case we're seeing right now is that North Korea's given a pretty specific timeline.