Why is it whenever a truly evil organization appears on the planet, the US does nothing to stop it? Or offers half-measures and equivocations while pursing its own tangential interests?
ISIS: Completely evil, both parties agree it needs to be destroyed. What does the US gov do? It offers support to allies of ISIS, doesn't send troops to fight it, and it actively fights against about half of the troops who fight ISIS (Syrian Regime, Hezbollah).
Boko Haram: Completely evil, both parties agree. What does the US gov do? Nothing. Literally nothing.
North Korea: Evil, both parties agree. Controls vast store of weapons, regularly threatens allies and the US with use of those weapons. Poses obvious threat. What does the US gov do? Economic sanctions, which have zero effect because NK never traded with US or allies of the US. Pressure china. Offer excuses. More bluster and propaganda.
Compare this to what was done to Vietnam, Bosnia, Greneda, Cuba, Iraq, Syria, Libya, Iran, Venezuela, etc etc etc who disagreed with US policy but were clearly not evil (or at least, not everyone agreed they are evil).