It is so sad how the past corrupt presidents of Nigeria who brought in corruption and hardship to Nigerians, and even taught Nigerians that looting is lucrative and even legalized it such that it has become a culture for every public office holder to loot and squander public funds meant for national development, why can't they be prosecuted and hanged or at least given up to 50yrs jail term despite their age now, so that even when they die, their corpses will be in jail. and also impoverish their families so that all Nigerians can see and know that truly we are out to clean the nation and move ahead with national development. why can't this be done by an incumbent president of Nigeria? Isn't this a sign that we have no hope of good governance?

It cannot be done by the incumbent President.
Reason is that our incumbent leaders are deeply meshed in the same corruption as their predecessors.
Secondly, they were CHOSEN by their predecessors and never elected by the citizenry.
So they remain eternally grateful for being chosen out of the 160 million pool.

you are very correct, that means we should rather work towards electing a peoples' president first!

Because both the judiciary and the police forces are in the pockects of THE CORRUPT!!!
So, who's gonna do the prosecuting?
God?

Those corrupt leaders are still in charge.

A cockroach will protect other cockroaches no matter what.

That means Nigeria is in a circle of DOOM!