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

I think it is safer for a country to have many different allies rather than rely on one very powerful relationship. In our daily lives, we've learnt how to not depend on one person for everything and it goes the same for countries. That one country will not always be there for you, will not always accommodate your needs nor is it guaranteed that that one country will not betray you.

For example, there are nations that has been betrayed by one their strongest and closest allies but has never reconciled since their fall out. The United States of America (one of the most powerful countries in the world, especially currently) and The Islamic Republic of Iran. The U.S provided the monarch with advanced weapons and nuclear technology through the 'Atoms for peace' program and other intelligence support. In 1979 the Islamic revolution took over the monarch which lead Iranian students to stormed the U.S embassy in Tehran and held 52 Americans hostages for exactly 444 days which then cause the U.S to shift its diplomacy and from then on till this day, the U.S sees Iran as the world's leading state sponsor of terrorism and a nuclear threat.

In this case is why I truly believe that a country should have many different allies who can help back them up in any case rather than relying on one very powerful relationship with one other country. It isn't just for the current moment of what the country needs but for the future of the country and its people as well that a country has more than one allies that they could rely on helping them. They could never guess whether that one very powerful country would truly stay loyal to them or not especially during a crisis where they're the victim.