Who to sink?

[fistfullofnails]

I started one of my first campaigns and was ordered to patrol a stretch of sea off the scandanavian coast. Being the mutinous scum that I am, I said "Screw that!", and went straight for the seas surrounding Britain. Eventually, after becoming tired of not seeing any ships that I thought would be fairgame, I decided to make my way directly into a small port. There I spied an American tanker at anchor. I went on to torpedo it till it laid at rest on the harbor bottom. I met no resistance and proceeded to make my way out to deeper waters afterwards. While leaving, I came upon a British schooner and used it as deck gun practice for my mates, telling myself it could have been being used for clandestine activities by the Brits. I then checked my sunk tonnages and after seeing it all composed of neutral entities, realized that it was 1939 and I guess war hadn't been officially declared yet. Whoops. Anyways, is there an in-game way of telling who is sinkable and who is neutral or off-limits? If I had obeyed orders to patrol the square of water I was told, would I have gotten more specific instructions on who or what to engage? I did some research and found the pic on the web below from https://en.wikipedia.org/wiki/Timeline_of_World_War_II_(1939). It is labeled as The allies and axis powers at the dawn of the German/Soviet invasion of Poland. Would it be safe to assume I can sink ships from these allied countries?
http://i1290.photobucket.com/albums/b531/bufaloeletric/300px-Ww2_allied_axis_1939_sep_zpsvjuyafu3.png

I understand that Britain did not enter the theater until around september of 1939. I wasn't paying attention to my calendar so I'm not really sure what date it was.

[Von Due]

If you start the campaign before Sept. 1st 1939 you will notice on the nav map that all countries are the same colour. Once the war breaks out, Poland turns red and Germany is blue while all others are green. Shortly after, Britain and France joins the war on the Polish side and they too turn red. Red is enemy and fair game. Blue is friendly, green is neutral.

Use the flags in the recon manual (when in doubt, together with the map's colours) to ID your potential target (you did remember to ID the target first?).

[fistfullofnails]

If you start the campaign before Sept. 1st 1939 you will notice on the nav map that all countries are the same colour. Once the war breaks out, Poland turns red and Germany is blue while all others are green. Shortly after, Britain and France joins the war on the Polish side and they too turn red. Red is enemy and fair game. Blue is friendly, green is neutral.

Use the flags in the recon manual (when in doubt, together with the map's colours) to ID your potential target (you did remember to ID the target first?).

I already knew the American flag, but looked up the variation of the British flag in the book. If there was something I needed to physically do in-game to verify my targets, I did not do that. Thanks for the info, I had no idea that the countries at war would be colored in the nav map. I'm obviously playing pre-sept. 1st.

[THEBERBSTER]

Hi ffon
America is a neutral until the Japan attack on Pearl Harbor in December 1941.
Germany then also declares war.
Peter
https://s7.postimg.org/shq5e949n/lsh3_support_download_banner.gif

[Von Due]

ID-ing a flag for nationality is a matter of getting close enough to see the flag on their mast or stern. Some mods however include unmarked ships that may or may not be enemy. That will be for merchants only AFAIK as all warships would fly their nation's flag.