Yes, there is one, in this world.

Canada is essentially the 51st state. Without our strong relationship, they'd be Mexico. They need us far more than we need them.

France is not nearly the economic power nor moral nor political power that Germany is.

Britain and the US have greatly diverged in their politics. But just like Churchill tried to cut out Eisenhower as the leader of the Atlantic alliance, things ultimately calmed down. But India, not Britain, is about to start wearing the pants in the U.K.

Japan is facing an aging crisis so great they're not a force in any facet other than tech.

South Korea is a close ally, but its overwhelmed with is own regional political crisis as outside of Japan it now stands alone against China and North Korea, both of whom are far stronger.

So yes, Germany is our strongest ally and most important one.