Is this genuinely in the interest of America, or just in the interest of the person making the decision? That's a question you always have to ask, but it seems particularly pertinent in the case of a leader who has been issuing numerous baseless complaints about various opponents, whose actions have repeatedly been refused by courts, and who was denied a second term.

So while it's true that the government doesn't need to act in the interests of anybody but its own citizens, it would be nice to know if this decision achieves even that much -- or if it's just spite.

That's absolutely true, which is why we have courts, representative legislatures, and elections. Methods of mitigating the corruption of the governing class are built into the system. It doesn't work quickly or perfectly, but it's better than autocracy.