What advantages did the North have over the South in the US Civil War?

The North
had international legitimacy. Other
nations recognized the North and could provide trade and
credit. The
Confederacy, on the other hand, never received international recognition.
While
Britain unofficially built commerce raiders for the South, the states
in rebellion could not
rely on international aid.

The
North had more fighting men than the South.
Eventually this would come to
bear in terms of both supplying men to fight as well as men to
provide
supplies and food to the armies. The South could not afford a long war of attrition.
The
quality of troops in the North increased as the war progressed, while the
South was taking the
young and the old to fill its ranks before the war was
over.

The North had
greater infrastructure. Railroads
allowed the North to ship men and supplies...