When there is a space that has one country's tank (Germany for example) and the same space on the board contains water between the enemy's land (UK for example), can the Germany tank attack UK...even though there is water between the two contries but they are in the same space? Or does the tank have to be transported even though it is in the same space?
Here's the snippet of map we're talking about:
There are three spaces of interest here:
These are three separate spaces, and must be passed through in turn; Western Europe is not adjacent to England. You can't just jump from Western Europe to England, you need to pass through the sea zone on the way there. Unfortunately, tanks can't enter sea zones except by boarding a transport.
So getting a tank from Western Europe to England looks like this:
A tank has to be carried over "water" by a transport. From there, it can debark on any "land" square adjacent to the transport's "stopping" square.
But the tank unit can't traverse water square by itself (without a transport).