Nuke now, nuke later - help me decide

This is only my 2nd game of Civ V (previously played all others). I'm in a multiplayer game. Two of us left. We are on separate continents. Never been at war with last opponent. My opponent has just sailed up to my coast with an unescorted aircraft carrier. Just one. Nothing else.

I notice that I can see what aircraft he has in his cities, should I be able to see what is in his carrier? Or is that normally hidden? There is no little number next to it indicating aircraft carried.

If the contents of a carrier is normally hidden then I suppose I have to assume he has 4 atomic bombs on board and I need to nuke him now. Or is the carrier empty and I can hold off from war? Is he just having a pleasure boat ride?

Should I be able to see if he has atomic bombs on board?
Thanks

Methinks that aircraft, if present, would be shown AS a number above the city or ship; thus, no number, no aircraft or nukes, no problem . ...

OTOH, if it is a 'scouting CV'(aircraft carrier), leading a chain of 'loaded' CVs, you COULD have a problem REAL SOON .

Thanks for that. I left the carrier alone. He sailed off. Armageddon has been averted. For now...

Above the city or ship the aircraft appears with a number , no aircraft or nukes.

Thanks, that's exactly what I needed to know. I'll know for next time - just as Civ VI is released!