International Trade and Markets
Other nations do access your market with import/export routes.
A good resource to export is one which you can create cheaply and sell to someone who has likely trouble creating that good for himself. That either means mass produced high end goods from industrial nations to not so industrial nations, or raw resources going to other way to feed the industry.
Or luxury goods that can only be produced locally like opium or coffee.
You can also change and modify the type of market which has an impact on trading and what not. Overall for example right now I am playing as Venezuela and I just created my first tools workshop – I have no tools being exported anywhere or bought because I have not yet created anything – either a production method or business or export that requires tools. I am in the process of changing that….
So the answer is yes, but also a little bit of no. Other nations can access you, but might not and your laws and factors influence this