Seize the means of production
It is possible to take, if a great power has made Foreign investments in the country, and the country is not in any sphere of influence. It removes all great powers investments, and will thus hurt them in the race for influence.
It is wise to take, if a great power has invested in the country, and it would be very bad if said great power sphered you. As an example Saxony nationalising Prussian investment to prevent the formation of North German Federation.