US intervention can be helpful in several circumstances. Firstly, when there's a clear case of humanitarian crisis or genocide, as seen in cases like Kosovo or the intervention in Rwanda. The US can help save lives and protect human rights.
Secondly, when international stability is at risk, such as during the Cuban Missile Crisis, the US successfully prevented a potentially catastrophic nuclear conflict. This shows how intervention can be essential in maintaining global peace.
On the flip side, US intervention can be ineffective or even destructive when it's perceived as driven by economic or geopolitical interests rather than humanitarian concerns. Instances like the Iraq War have illustrated how military interventions based on questionable intelligence can lead to destabilization and loss of life. Also, interventions without adequate post-conflict planning can result in prolonged instability, as seen in Afghanistan.
In summary, the effectiveness of US intervention in international conflicts depends on clear justification, international consensus, and a well-planned approach with post-conflict stabilization efforts. It should prioritize humanitarian concerns and global stability over unilateral strategic interests.