Just War, by Murray Rothbard, is essential reading. It’s probably a 30-60 minute read, depending on how fast you go though it or ponder it. As with almost all things, I don’t accept many of the implicit premises. However, I do agree that Rothbard’s political and legal logic within the confines of the premises is pretty consistent.

The main idea advanced by this essay is that America has only fought been involved in two just wars: The American Revolution and Southern Independence (The "Civil War"). In other words, and he lays out a pretty good argument, the Southern States were conducting a just war against the unjust North for pretty much the same set of justifiable reasons the American Revolutionaries waged a just was against the unjust British crown. It’s certainly not a new idea that the South was right — Southerners being Southerners — but the just reasons they had to go to war have always been overshadowed by the slavery issue. After all, the North won and the winner gets to write and teach history.

A few key excerpts:

…a just war exists when a people tries to ward off the threat of coercive domination by another people, or to overthrow an already-existing domination. A war is unjust, on the other hand, when a people try to impose domination on another people, or try to retain an already existing coercive rule over them.

[…]

There have been only two wars in American history that were, in
my view, assuredly and unquestionably proper and just; not only that,
the opposing side waged a war that was clearly and notably unjust. Why?
Because we did not have to question whether a threat against our
liberty and property was clear or present; in both of these wars,
Americans were trying to rid themselves of an unwanted domination by
another people. And in both cases, the other side ferociously tried to
maintain their coercive rule over Americans. In each case, one side –
"our side" if you will – was notably just, the other side – "their
side" – unjust.

To be specific, the two just wars in American history were the American Revolution, and the War for Southern Independence.

[…]

These 13 separate republics, in order to wage their common war
against the British Empire, each sent representatives to the
Continental Congress, and then later formed a Confederation, again with
severely limited central powers, to help fight the British. The hotly
contested decision to scrap the Articles of Confederation and to craft
a new Constitution demonstrates conclusively that the central
government was not supposed to be perpetual, not to be the sort of
permanent one-way trap that Grotius had claimed turned popular
sovereignty over to the king forevermore. In fact, it would be very
peculiar to hold that the American Revolutionaries had repudiated the
idea that a pledge of allegiance to the king was contractual and
revocable, and break their vows to the king, only to turn around a few
short years later to enter a compact that turned out to be an
irrevocable one-way ticket for a permanent central government power.
Revocable and contractual to a king, but irrevocable to some piece of
paper!

And finally, does anyone seriously believe for one minute that
any of the 13 states would have ratified the Constitution had they
believed that it was a perpetual one-way Venus fly trap – a one-way
ticket to sovereign suicide? The Constitution was barely ratified as it
is!

So, if the Articles of Confederation could be treated as a scrap
of paper, if delegation to the confederate government in the 1780s was
revocable, how could the central government set up under the
Constitution, less than a decade later, claim that its powers were
permanent and irrevocable? Sheer logic insists that: if a state could
enter a confederation it could later withdraw from it; the same must be
true for a state adopting the Constitution.

And yet of course, that monstrous illogic is precisely the
doctrine proclaimed by the North, by the Union, during the War Between
the States.

In 1861, the Southern states, believing correctly that their
cherished institutions were under grave threat and assault from the
federal government, decided to exercise their natural, contractual, and
constitutional right to withdraw, to "secede" from that Union. The
separate Southern states then exercised their contractual right as
sovereign republics to come together in another confederation, the
Confederate States of America. If the American Revolutionary War was
just, then it follows as the night the day that the Southern cause, the
War for Southern Independence, was just, and for the same reason:
casting off the "political bonds" that connected the two peoples. In
neither case was this decision made for "light or transient causes."
And in both cases, the courageous seceders pledged to each other "their
lives, their fortunes, and their sacred honor."

[…]

In his First Inaugural, […] what he [Lincoln] was hard-line
about toward the South was insistence on collecting all the customs
tariffs in that region. As Lincoln put it, the federal government would
"collect the duties and imposts, but beyond what may be necessary for
these objects, there will be no invasion, no using of force against . .
. people anywhere." The significance of the federal forts is that they
provided the soldiers to enforce the customs tariffs; thus, Fort Sumter
was at the entrance to Charleston Harbor, the major port, apart from
New Orleans, in the entire South. The federal troops at Sumter were
needed to enforce the tariffs that were supposed to be levied at
Charleston Harbor.

Of course, Abraham Lincoln’s conciliatory words on slavery cannot
be taken at face value. Lincoln was a master politician, which means
that he was a consummate conniver, manipulator, and liar. The federal
forts were the key to his successful prosecution of the war. Lying to
South Carolina, Abraham Lincoln managed to do what Franklin D.
Roosevelt and Henry Stimson did at Pearl Harbor 80 years later –
maneuvered the Southerners into firing the first shot. In this way, by
manipulating the South into firing first against a federal fort,
Lincoln made the South appear to be "aggressors" in the eyes of the
numerous waverers and moderates in the North.

Outside of New England and territories populated by transplanted
New Englanders, the idea of forcing the South to stay in the Union was
highly unpopular. In many middle-tier states, including Maryland, New
Jersey, and Pennsylvania, there was a considerable sentiment to mimic
the South by forming a middle Confederacy to isolate the pesky and
fanatical Yankees. Even after the war began, the Mayor of New York City
and many other dignitaries of the city proposed that the city secede
from the Union and make peace and engage in free trade with the South.
Indeed, Jefferson Davis’s lawyer after the war was what we would now
call the "paleo-libertarian" leader of the New York City bar,
Irish-Catholic Charles O’Conor, who ran for President in 1878 on the
Straight Democrat ticket, in protest that his beloved Democratic
Party’s nominee for President was the abolitionist, protectionist,
socialist, and fool Horace Greeley.

The Lincoln Administration and the Republican Party took
advantage of the overwhelmingly Republican Congress after the secession
of the South to push through almost the entire Whig economic program.
Lincoln signed no less than ten tariff-raising bills during his
administration. Heavy "sin" taxes were levied on alcohol and tobacco,
the income tax was levied for the first time in American history, huge
land grants and monetary subsidies were handed out to transcontinental
railroads (accompanied by a vast amount of attendant corruption), and
the government went off the gold standard and virtually nationalized
the banking system to establish a machine for printing new money and to
provide cheap credit for the business elite. And furthermore, the New
Model Army and the war effort rested on a vast and unprecedented amount
of federal coercion against Northerners as well as the South; a huge
army was conscripted, dissenters and advocates of a negotiated peace
with the South were jailed, and the precious Anglo-Saxon right of habeas corpus was abolished for the duration.

 

While it is true that Lincoln himself was not particularly
religious, that did not really matter because he adopted all the
attitudes and temperament of his evangelical allies. He was stern and
sober, he was personally opposed to alcohol and tobacco, and he was
opposed to the private carrying of guns. An ambitious seeker of the
main chance from early adulthood, Lincoln acted viciously toward his
own humble frontier family in Kentucky. He abandoned his fiancée in
order to marry a wealthier Mary Todd, whose family were friends of the
eminent Henry Clay, he repudiated his brother, and he refused to attend
his dying father or his father’s funeral, monstrously declaring that
such an experience "would be more painful than pleasant." No doubt!

Lincoln, too, was a typical example of a humanitarian with the
guillotine in another dimension: a familiar modern "reform liberal"
type whose heart bleeds for and yearns to "uplift" remote mankind,
while he lies to and treats abominably actual people whom he knew. And
so Abraham Lincoln, in a phrase prefiguring our own beloved Mario
Cuomo, declared that the Union was really "a family, bound indissolubly
together by the most intimate organic bonds." Kick your own family, and
then transmute familial spiritual feelings toward a hypostatized and
mythical entity, "The Union," which then must be kept intact regardless
of concrete human cost or sacrifice.

Indeed, there is a vital critical difference between the two
unjust causes we have described: the British and the North. The
British, at least, were fighting on behalf of a cause which, even if
wrong and unjust, was coherent and intelligible: that is, the
sovereignty of a hereditary monarch. What was the North’s excuse for
their monstrous war of plunder and mass murder against their fellow
Americans? Not allegiance to an actual, real person, the king, but
allegiance to a non-existent, mystical, quasi-divine alleged entity,
"the Union." The King was at least a real person, and the merits or
demerits of a particular king or the monarchy in general can be argued.
But where is "the Union" located? How are we to gauge the Union’s
deeds? To whom is this Union accountable?

The Union was taken, by its Northern worshipers, from a
contractual institution that can either be cleaved to or scrapped, and
turned into a divinized entity, which must be worshipped, and which
must be permanent, unquestioned, all-powerful. There is no heresy
greater, nor political theory more pernicious, than sacralizing the
secular. But this monstrous process is precisely what happened when
Abraham Lincoln and his northern colleagues made a god out of the
Union. If the British forces fought for bad King George, the Union
armies pillaged and murdered on behalf of this pagan idol, this
"Union," this Moloch that demanded terrible human sacrifice to sustain
its power and its glory.

For in this War Between the States, the South may have fought for
its sacred honor, but the Northern war was the very opposite of
honorable. We remember the care with which the civilized nations had
developed classical international law. Above all, civilians must not be
targeted; wars must be limited. But the North insisted on creating a
conscript army, a nation in arms, and broke the 19th-century rules of
war by specifically plundering and slaughtering civilians, by
destroying civilian life and institutions so as to reduce the South to
submission. Sherman’s infamous March through Georgia was one of the
great war crimes, and crimes against humanity, of the past
century-and-a-half. Because by targeting and butchering civilians,
Lincoln and Grant and Sherman paved the way for all the genocidal
honors of the monstrous 20th century. There has been a lot of talk in
recent years about memory, about never forgetting about history as
retroactive punishment for crimes of war and mass murder. As Lord
Acton, the great libertarian historian, put it, the historian, in the
last analysis, must be a moral judge. The muse of the historian, he
wrote, is not Clio, but Rhadamanthus, the legendary avenger of innocent
blood. In that spirit, we must always remember, we must never forget,
we must put in the dock and hang higher than Haman, those who, in
modern times, opened the Pandora’s Box of genocide and the
extermination of civilians: Sherman, Grant, and Lincoln.

Perhaps, some day, their statues, like Lenin’s in Russia, will be
toppled and melted down; their insignias and battle flags will be
desecrated, their war songs tossed into the fire. And then Davis and
Lee and Jackson and Forrest, and all the heroes of the South, "Dixie"
and the Stars and Bars, will once again be truly honored and remembered.

The above, though a lot of excerpts, is just a scratch on the surface.