Computer security what do you think is harder offense or defense?

Most defiantly defense is harder. You have to try to protect yourself from many different vulnerabilities. It is like a Soccer goalie trying to guard the net from the whole opposing team kicking hundreds of balls at him. Also with the advancements of technology it opens more opportunities to be attacked. (that would be like extending the goal to make it bigger)

I agree - defense is much harder. However, it starts with planning.

You won’t know about an attack until after you KNOW about it - whereas the attacker gets to plan on when to attack and how – that by itself is a huge benefit to being on the BLACK side of that game.

While it sounds trite to say - keep the machines patched and updated, keep a good AV product running, choose GREAT PASSWORDS, watch your logs and monitor system changes, not any one of these makes it an easy process. Doing them all can be time consuming and one of the things I see more than anything else is that log files are possible to give you clues, but if you are not looking at them, then activities from the bad guys can go unnoticed for weeks/months/years.