Is it safer for a country to have many different allies or to rely on one very powerful relationship?

I think we should have all different allies instead of one because if one of the country's have to go on war than lot's of people can help than one big country as a pair of two at risk of one getting takeing other and being on there own with no help to fight if there in a war. so if we have lots of small Islands or country's we can be strong all together in one big community to helping each other to avoid risk at war and deaths. A other good reason is if you are wive one big country and nothing else what if that country dose not want to be wive you anymore and goes away from your country than you lose everything of help and other stuff like that . But if you have lots of country's than if one goes we still have lots of things to survive and lots of people to help.