The Dred Scott case was an interesting and complex one in and of itself (not least because of the involvement of Justice Taney, a wonderfully intriguing figure), but I'm most interested here in what part the ruling played in the deterioration - already well on its way I'm aware - in political and judicial cooperation between North and South and the ultimate decision to go to war. How did it exacerbate existing tensions? Did it bring anything new to the table? What impact, in any, did the politicisation of judicial and legal decisions in the Dred Scott and the slave court cases which preceded it have on increasing tensions and decreasing the likelihood of an amicable agreement being reached?
Its biggest impact was probably in galvanizing abolitionist sentiment in the north. This, along with the earlier Fugitive Slave Act and the Kansas-Nebraska Act (which unleashed the Bleeding Kansas fiasco) stirred up the northern states and buoyed support for the fledgling Republican party. It was perceived that the South, by use of threats, political stratagems, and, in this case, a Supreme Court that was packed with Southerners (five out of seven of the concurring justices were Southerners), was forcing tacit acceptance of slavery down the rest of the country's throat. After this, there was far greater reluctance to compromise on the issue of slavery. The door was open, it seemed, for slavery to be declared legal in every state in the Union, at least de facto. For, if a man can keep his slaves in a free state for an indefinite "sojourn," and the Federal government has no authority to regulate or prevent slavery in the territories, it's not that far a leap to out-and-out legalization.