a consequence of of using the tactic that uses icbm and nuclear tests. It's a huge achievement that Trump got UN and China in joining the sanction. Cancelling joint military exercises is a concession from U.S. side, but it's is not as big as that, say if we cancel maximum sanction (actually we haven't reach maximum sanction, there is still room to sanction NK). North Korea made concession too, stopped nuclear test. We're not repeating the mistake we made before. Economic sanction is key, it is our principle. Trump isn't going to give it up.
As for Trump wants agreement, Trump already said he's willing to talk to Kim in person during presidential campaign. This signal is clear to North Korea before they made a serious of test in the spring & summer in 2017. Again, everybody knows how to show your strength before talking to your enemy. It's all for talk, not for war. This is just basic 101. Iran is doing same today.