Detroit's motto

[Huggybear]

Is it speramus meliora [[indicative: "we hope for better things")

Or sperimus meliora [[hortatory subjunctive: "let us hope for better things")?

I've seen it written both ways. CAYMC has the first version; one of the plaques on a Belle Isle footbridge has the second. Old seals seem to have the first version.

Either would be correct in Latin, but I guess the question is: which is more in line with the attitude of people here? And was the Belle Isle version the product of a person's learning the phrase in Latin, remembering it in English, and then working his way back to Latin?