History shows us that we should not play things halfway.
Toyotomi Hideyoshi was Undisputed Ruler of Japan. He had brought all the Japanese generals under his loyalty, set an extremely durable and efficient legal structure, and had achieved more than anyone in Japanese history - rising from a peasant servant to the height of command.
Unsatisfied with the fastest and largest ascent in all of Japanese history, Hideyoshi wanted to conquer all of Korea and China. In the year 1597, he launched the Second Korean Campaign.
In the most desperate times, strong cultures produce great heroes - and Korean Grand Admiral Yi Sun-Sin rose to the challenge, shattering the Japanese naval forces and cutting the supply lines. The Japanese forces pinned down in Korea had land superiority, solid defensive fortifications, and better artillery. But the Ming China/Joseon Korean alliance was winning the gradual war of attrition after establishing naval superiority.
Toyotomi had won basically every engagement he'd fought in throughout history. A scuffling defeat here and there, but he had seemed blessed by the gods themselves. He was, naturally, furious at the inability of his forces to conquer Korea.
And thus, blunder is about to become layered on top of blunder. The chief of the Second Korean Campaign was Kobayakawa Hideaki, who, just three years later, will betray and break the back of the Toyotomi at the decisive battle, sealing their fate and consigning them to the ash heap of history.
But at the time, Hideaki was still a loyal Toyotomi general.
Back in Japan, Hideyoshi Toyotomi is furious that the campaign is failing, and he dispatches Isida Mitsunari to inspect what the hell is going on in Korea.
Now, my thoughts on Mitsunari have evolved over the years. At first he seemed the greatest sort of blunderer. Perhaps that's true - he sure did blunder - but I've come to a greater understanding of him than a casual read of history would suggest. His blunders are due to the fact that he was an exceedingly honorable and honest man. Pragmatic? No. Not pragmatic. But exceedingly honest and honorable.
Mitsunari, in honest-but-abrasive Mitsunari fashion, shouts at Hideaki. Mitsunari goes to Japan and reports to Hideyoshi. Hideyoshi wonders why the hell the Japanese forces haven't won. Mitsunari blames Hideaki.
And herein comes the mistake. Okay, the Toyotomi forces lost in Korea. Hideaki was a formerly loyal general and had a mixed campaign record - he fought well on land and it's not really his fault that Korean Admiral Yi smashed the Toyotomi Naval Forces. But then, he was the commander and they did lose.
You could make the case for executing Hideaki, if you believed he was negligent in his duties. Or you could let him return to his post as a loyal Toyotomi vassal, which he was before the war.
But instead, they played it halfway. Hideaki was demoted and disgraced and lost 2/3rds of his income and much of his land.
Huge mistake.
We can turn some thousands of miles westwards to Europe for a perspective. In "The Prince," Machiavelli says, "You must pardon a man or crush him completely. A man does not forget a small insult."
Hideaki was at the weakest position of his life following the failure in Korea. Forcing him to commit ritual suicide would have been accepted as a necessary measure. His lands could have been given to another loyal general, or even let his son inherit, "the slate being cleansed" by the father's honorable death.
Machiavelli says again, "Do violence if you must, but do not take the people's lands. A son is more likely to forgive the murder of his father than the seizing of his inheritance."
In any event, Machiavelli might be a little too hardcore, but the general point stands - don't go halfway. Pardon Hideaki? Okay. Execute Hideaki? Okay. Insult and demean him, and then give him time to rebuild and consolidate? Not okay.
Toyotomi Hideyoshi dies shortly afterwards, and Hideaki - who had been loyal, despite the failure in Korea - manages to recover from disgrace, rebuild, and reclaim his lands.
Eventually, the Toyotomi break into two factions - one led by Tokugawa Ieyasu, the other led by former Inspector-General Mitsunari. You know, the one who shouted at Hideaki, made him lose favor, and encouraged the demotion and his lands being seized.
You can see where this is going.
At this point, it still might have been possible for Mitsunari to have Hideaki assassinated, or to lay a trap for him of some sort before the fighting breaks out. But Mitsunari instead promotes Hideaki to a top post during the Civil War.
At the Battle of Sekigahara, the decisive battle in Japanese history, it's a bit of a mystery why the Tokugawa forces are even willing to fight. They have the low ground, in the valley, with Mitsunari's forces having a better high-ground position and being more well-rested. It's pouring rain, so the Tokugawa could absolutely withdraw.
Why are they staying and fighting?
As the battle starts, Kobayakawa Hideaki - occupying the highest position overlooking the front lines of battle - hasn't moved. At noon, he defects and opens fire on his own side. Caught between the Tokugawa forces on land, and being gunned down by artillery and rifle fire from behind their own lines, Mitsunari's forces collapse and the Toyotomi are destroyed.
Tokugawa keeps Hideaki at arm's length for the rest of his life. He orders him to immediately pursue and destroy the Western forces, working as his vanguard. For his part in the destruction of the Toyotomi, he's allowed to keep his lands and given a small additional stipend and no significant role in the Tokugawa government that followed.
The history books say that he went insane before dying.
You can pardon an old friend who has done wrong. You can crush him. But you can't insult him. Playing things halfway has always, and will always, lead to very bad outcomes.