What was the importance of the USS Monitor vs the CSS Virginia?

The two ironclad warships, the South's CSS Virginia and the North's USS Monitor, engaged in a naval battle "first". It was the first time two ironclads fought each other in naval history.

Ironically, the CSS Virginia was a resurrected USS ship called the Merrimack that was burned during a Federal retreat from Norfolk earlier in the war.

The importance was far reaching and also a short term shock event. The CSS Virginia's attack on Federal warships to support Union General McClellan's "peninsula campaign" to attack Richmond was a huge set back. The Union's wooden warships were sunk by the CSS Virginia.

Now while the battle of the Monitor & Virginia was a draw, it showed the Union that ironclad warships were needed during and after the war.