No one has mentioned "going on the offensive" but YOU. The thread is clearly about self defense in one's HOME. No one has advocated room clearing in random strangers homes.
And now you bring up "going on the offensive when there is no threat.."
WHAT THE HECK are you talking about?
If you don't consider someone invading your home as a threat.......good grief man.
The OP and everyone else in this thread (but you) understand that intruders in their home IS A THREAT. You feel that the homeowner should hunker down behind the bed and call 911. That's a great idea until you think about what an intruder (or intruders) could do to your home, your property or........your family while you wait for the police to arrive. How long is your LE response time? The average police response time is TEN MINUTES.
I'm sure most would consider an intruder in the home to be a threat and dealt with accordingly.
If you think clearing rooms IN YOUR HOME is going on the "offensive" I pity your family.