Would an E9 comply if ordered to attention by an O1?

Yes, but the LT would be ansering to a higher command.

An officer is an officer.

According to the UCMJ and the oath, technically the E9 should. However, not too many lower echelon officers are that stupid.

Yes he is suppose to but better have a sack on you to do it

He should reply but I'm sure the commander would tell that butterbar to back off

I was walking from the LSA to work along a road we called sniper alley (for a reason) on Camp Victory Iraq back in 2003. A reserve 2LT walks pass me (a PV2 at the time), I do not slaute but instead say the greeting of the day. He stops and calls me back to him insisting a salute. I oblige and say "Roger, sniper check sir." rendering a bold and over the top salute.

Just behind him was the General and CSM. The General walks up to me with the CSM right behind him. I think I am about to get ripped apart. The General says "Did that LT just tell you to salute him?" I said yes sir. He smirked, "Fuckin Lieutenants." and walked away. The CSM patted me on the back and gave me the same smug smile and followed the General.

When I got to work I told my section who didn't believe me! But who would? If I wasn't there I wouldn't have believed it my self.

An O1 (Ensign -Navy) and an E9 (Master Chief- Navy) crossed paths in a Training command; the O1 stops and sees that he wasn't saluted and Turns around to the E9 to say "excuse me Master Chief did you forget something?" , The Master chief looks back perplexed then says "Oh I suppose I did", Master Chief reaches into his pocket and pulls out a Navy Coin and Tosses it to the O1, "Here" he says!, "tell your mother you met a real sailor today!" then goes about and carries on with his day.

Well of course the E9 is going to acknowledge and abide by customs and courtesies, but I can also promise the E9 is going to be having a talk with someone else that easily out ranks that butter Bar and hinge will be very different.

The other day I was walking through BN HQ and I saw this boot walking over in alphas with his firewater ribbon and shooting badge. As we crossed paths he goes, "good morning gentlemen" my buddy simply said "hey" I said "what's up man" and continued walking. Assuming he was a pvt who just got to the fleet I didn't think much of it until I looked behind me and noticed the butterbars on his shoulders. Well sir... the tables have changed lol

Yes