I am sorry, but the US has not relied on diplomacy since Colin Powell lied to the UN.

Do you know who the "top diplomat" in the US Government is? Anthony Blinken.

Have you EVER heard Blinken call for negotiations with Russia?

All he does is call for more war, more weapons, more violence:

"Veteran diplomats question Blinken’s ‘do not engage’ strategy"

https://responsiblestatecraft.org/2022/07/15/diplomacy-watch-veteran-diplomats-question-blinkens-do-not-engage-strategy/

North Korea? That was just a glimmer, with Trump - a short lived anomaly, because Trump did not subscribe to the "American Empire" philosophy.

Nonetheless, John Bolton, the "veteran American Diplomat" and former UN Ambassador, was there to sabotage the talks and make sure that nothing came of them.

https://www.moonofalabama.org/2018/05/how-john-bolton-sabotaged-the-north-korea-summit-.html?cid=6a00d8341c640e53ef0223c84daa50200c