Why was a union victory at vicksburg so important for the north

The union victory at Vicksburg was important for the north because the Union army captured the last Confederate stronghold on the Mississippi River, completing the Northern Strategy. It is described as the turning point of the war and cut off the states of Arkansas, Louisiana and Texas from the Confederacy and the Confederate army was driven back into their defensive lines.

You don’t list any options but the one that frets overspending and the consequences of that.