Interesting subject, I do have two remarks regarding it:

• ''Sometimes only way to defend truth or justice is via arrogant behavior. ''
  Yes, sometimes. But I am pretty sure more often than not it is wise to be rational and open for discussion. If you are right, or just, why do you even need to reveal arrogant behavior? Your arguments should speak for itself.
• Arrogance in itself is a neat characteristic to have, as it will motivate you to go even further. But expressing it has potential risks surpressing your ability to learn from others. Arrogance witholds others to express themselves about a subject, while you have no idea what they have to say. Others can show you different perspectives on a situation like which you've never looked at it before, nonetheless, perception is everything.