Uzushiogakure is the strongest village kushina, minato, naruto, and posibly the uchica's and hyuaga's
****, how can people be so damn stupid. He isn't asking which village produced the strongest ninjas, but which is the strongest village of them all. Since Uzushiogakure was destroyed, it isn't the strongest, it's
gone, kaput, dead. If a stray cat decided to declare war on Uzushiogakure, the cat would win because the village doesn't
exist.
But back on topic, imo Konoha is the strongest village. It's the biggest, has the most manpower and the largest ninja force, with lots of capable ninja and some really excellent ones, including Naruto, the ninetail's jinchuuriki. It also is located in a central position in the largest country of them all, and, unlike wind country which is basically a big desert or lightning country which has lots of mountain ranges, fire country actually has forests, a very important resource. So, we can deduce that in a war situation it would have the best chance at maintaining the war effort and therefore winning.