The basic premise of Sowell's column is that pacifism incites war and war leads to peace. This may sound Orwellian, and it is, but the argument behind it is sound enough to have convinced many intelligent people. It's sort of similar to the logic of permissive concealed carry laws. The only way to counteract force is with force. There is a certain truth to this. If you are attacked and do not resist you will be overwhelmed.
The problem with this kind of thinking is that using force to counteract force has unintended consequences. For one thing it leads to escalation. If everyone carries a knife then some people will start to carry guns. If everyone has a gun then some people will seek out automatic weapons. Currently the escalation stops at nuclear weapons, but part of the reason for their spread is that countries like Iran do not want to end up bringing a knife to a gun fight should conflict ever break out. The doctrine of disarmament argues, in part, that if the superpower(s) surrender their nuclear weapons then other countries are less likely to seek them out to even the playing field.
The other problem with using force to counteract force is that people do not exist outside of their social networks. Killing one person is never as simple as just killing that person. You are also killing someone's cousin, someone's brother, someone's son, someone's father. This breeds resentment and blood feuds. Right now Israel is bombing Lebanon back to the stone age, and while hundreds of Lebanese are dying thousands more are developing resentments against Israel that will last for the rest of their lives.
If Sowell's treatise, that force as a response to force brings peace, were true then WW II would never have happened. World War I involved a hell of a lot of force brought to bear against Germany, which had its population of young men decimated and its economy brought to its knees. 20 years later the Germans were back and looking for revenge, stronger and meaner than ever. Destruction may buy temporary peace, but it's at a terrible cost.
The reason we will never see a German lead WW III is because at the end of WW II the leaders of the victorious allies realized that force and vindictiveness would buy only temporary peace, at best. Just as important to the ultimate victory of WW II as the bombs and soldiers was the rebuilding effort. The Marshall Plan was one of the greatest acts of military strategy ever devised. It, along with the rebuilding of Japan, helped turn two aggressive violent powers into peaceful prosperous societies no more likely to attack their neighbors than Great Britain or France.
Pacifism is not an answer to aggression, Sowell's right, but what he leaves out in his analysis is that force is not a complete answer either. The actual way to achieve lasting peace is through a combination of force and compassion. The enemy must be destroyed, but then those left afterwards must be offered a better future than the one vengeance would provide. Israel's bombing the shit out of Lebanon is no worse than what the Allies did to Germany, but the difference is that Israel will not spend the money to rebuild and repair. It will simply leave the country a shattered wreck of a place where resentment and revenge can breed and grow. Even if Hezbollah is wiped out this time it will come back. It will keep coming back until the options for young men are better than joining Hezbollah. The same thing's going on Iraq
That is why those of us who are against these uses of force cringe and cry at the senseless slaughter. It's not going to change anything. Somewhere along the line we, as a society, forgot the lessons of history and came to believe that killing alone could solve our problems. It can't. You need more than just killing.
Of course there's also the matter of the individual lives lost and their value. We should oppose force because it means the deaths of innocents, and while that's sometimes unavoidable it is always tragic and horrific and should always be opposed and mourned. Force is sometimes necessary, but it has horrific implications and it is not enough. This bombing, the war in Iraq, both are terrific wastes of time, resources, and lives. That is something to be opposed.