Can walls stop mobs from entering my town?

A recent update added Cobblestone Walls, which are basically cost effective decorative fences that prevent players from jumping over it.

I'm wondering if these same walls can protect me from mobs like creepers, spiders, and skeletons.

Thanks!

What are cobblestone walls?

Cobblestone walls are a decorative alternative to fences. They come in two varieties, cobblestone walls and mossy cobblestone walls. They are made by placing cobblestone or mossy cobblestone in a Crafting Table like so. S is a cobblestone/mossy cobblestone block, and E means empty.

S S S
S S S
E E E

How high are cobblestone walls?

Since their properties are very similar to fences, they are 1.5 blocks high. Nothing can jump it unless there is a half-slab, block, or other item close enough to the wall to be able to jump over it. Therefore, it is recommended to use them in a flat area.

They are also good for bridges on maps like Skyblock, where you would have to make bridges that people/mobs may fall out of.

Pros

• It give you a better view than having two cobblestone/other material, since that would obstruct your view.
• Fences can be burned by griefers, nearby lava, and so on, whereas this cannot be burned. Additionally, it would take a long time for griefers to break it since it is made of cobblestone.

Cons

• Mobs such as Spiders and Spider Jockeys can climb over it.
• Endermen can teleport into a 'secure' area.
• If they are close to the wall, Creepers/TNT can blow it up.
• Skeletons/players with a bow can shoot arrows over the fence.

Miscellany

To stop Spiders and Spider Jockeys, you can place a block on top of the wall. If you still want to see, use glass. When used with burning netherrack, you can make a nice alternative to torches.

Cobblestone Walls works the same as Fences. It will prevent all non-flying mobs except spiders from climbing over. Enderman can also teleport pass Walls or Fences.

You can place a block/slabs/stairs to prevent spiders from climbing over.

To prevent Enderman from getting in, you need to have a roof that is not higher than 3 block.