During a recent interview, former Obama administration National Security Council spokesman Tommy Vietor cautiously stated that no progress was made with regard to North Korea during the last eight years:

HOST: Do you think, looking back now with everything that's going on with North Korea, if President Obama had anything to change about his policies with North Korea, do you think he would change anything, or would he have stayed course?

VIETOR: That's a good question. I mean, I think you can't look at the situation and say, "Yeah, he would have stayed the course," right? Because we didn't achieve what we needed to achieve, which was to stop their nuclear program.

It's interesting, I was listening to an interview that former Secretary of Defense Bill Perry did — Clinton's Secretary of Defense — and they had started in like the late 90's and early 2000's this diplomatic track with North Korea that they felt like was on the precipice of getting some sort of breakthrough. Then the Bush administration, because the Koreans were actually cheating, ended up walking away from it, thinking they should punish them.

... and then, you know, we just never got to a place where any progress was made, you know? I mean this thing was just always cranking along. We got sanctions put on them; we tightened down a whole bunch of sanctions, but that's an input, it's not an output, right? There was no — nothing progressed in the way we wanted as a result of those sanctions.