The good we did in the 20th Century was to bail out Europe from a war that was so convoluted very few make sense of it today! We did manage to get thousands of our young men killed in order to save France’s bacon!
WWII was one where our fearless leader goaded the axis powers into an act of war. The goading began a decade or so earlier when FDR boldly informed Britain to drop Japan as one of their key allies. They did and Tokio knew why and hated us and the Brits ever since. Of course this is just one of many.
The end of the war left China in the hands of the evil Mao to kill as many millions of his own people as he could.
We left battered Eastern Europe in the hands of the cruel Stalin to make their lives as miserable as they were under Hitler.
In Korea we stalemated and left the evil power in the North free to cause us mischief and to receive bribes for playing nice, which they never did.
In Viet Nam we lost.
We shouldn’t have invaded Iraq.
We should have bombed the hell out of Afghanistan and destroyed the oil fields of the sly Saudis and not placed troops on the ground to be maimed purposely so they could bring their damaged bodies back to America to show the fruits of war against islamists.
Now our great foreign policies pump money into nations that hate us. This is money we borrow from the Chinese who also hate us.
What good have we done? What have we lost excepting our honor?
This comment pertains to your check list of the wars we have gotten into.
By the time the fascists had ascended to power in Germany and elsewhere, the U.S. and remaining democratic countries of the world were correct to conduct themselves as though warned of imminent danger. The Nazis were national socialists, and hated democratic capitalism, as well as hated democratic socialism. So, all democrats were imperiled.
Were we to turn the clock back, to the vindictive Treaty of Versailles, I agree with the Republican analysis that had opposed that treaty (also John Maynard Keynes).
Having said this, most wars are indeed miscalculations. The French, nowadays, being an effete nation, and knowing that couldn’t fight any real war, play geopolitical games without much risk of getting sucked into war. We, not yet realizing we are fast becoming like France, run the risk of getting sucked into war when we play geopolitical games.
Now I will connect your rundown of wars to your original post (on the Civil War):
In your rundown of wars, I don’t see an argument that it was O.K. for South Carolina to bomb Fort Sumter. Why, if getting into war is usually a bad thing, wasn’t it a mistake for South Carolina to bomb Fort Sumter? You’re not saying that states that secede from the Union can violently seize the property of the Federal government within their territory, without offering compensation? Is it that you believe only property in slaves warrants compensation, not property in land and buildings?
Finally, I will ask you about sovereign default as a justification for war. At the time of the U.S. Civil War, Mississippi was in default of its debt to Northern and European creditors. Under the Constitution, the Federal government and all the other states are pledged to defend all the states of the Union from invasion. Accordingly, Britain did not invade Mississippi for default on its debt, which it was in the habit of doing back in those days. Once Mississippi left the Union, its creditors, among them Northern capitalists, were free to invade them.
Of course, in line with the doctrine of states rights, Jefferson Davis, when he was a Senator, said states could repudiate state bonds. The doctrine of states rights, as expressed by Davis, is a doctrine of state power over the doctrine of God-given individual rights, and is not to be confused with endorsement of a federal system of government. Do you agree with Davis? Property in state bonds isn’t sacred, only property in slaves?