Does the fate of the League of Nations show that the UN cannot prevent major international conflicts /?

Question

I would like my answers to contain critical analysis of the United Nations, its weaknesses, successes and likely reform. Also i would like the answers to evaluate the role of the League of Nations. Critical analysis if the United Nations can prevent the eruption of major international conflicts.

Answer 1

Well, we invaded Iraq when most of the united nations was against the plan.  What does that tell you

Answer 2

NO, it shows that a without the participation of the United States, the League was unable to prevent major international conflicts.

I suggest that the UN does a good job at preventing conflicts.  We do not know how many conflicts are preventing by the simple fact that nations have a place to negotiate outside the public eye.

Look at the 53 years of  UN history.  How many "major" conflcits were there?