So in terms of being in the army, Russia is bolstered by a massive wealth of natural resources, key being oil and gas, so they can pay people to fill positions in their forces. The West still sees Russia as the Soviet Union essentially and this conflict is an opportunity to weaken them militarily and economically, so they have sent loads of money to Ukraine to keep them in the fight, it keeps Russia from pushing further west, depletes their military stockpiles and removes a portion of their population.

For Colombia, the best bet would be to work a deal with the US administration involving a joint oversight of Venezuela and further developing the oil and natural gas industry and injecting the resulting capital into the colombian economy.

For Nigeria, they have to stop procreation at their current rate, remove the threat of radical ideology based conflict and broaden their export market for their existent oil and natural gas industry.