On 1 Feb 2016, at 17:18, xxxxxx@mail.de wrote:
> In Traveller Terms, however, how is it different from offering favorable conditions for a world to join the 3I?

It must be different or you would have used the European Union admitting the former eastern block countries as example 3.
;-)

Buying your opponents is an excellent strategy in the Civilisation computer game - indeed the Ankh-Morporkian school of conquest ("We can rule you wholesale") is my preferred solution.

In the real world, countries contain people, which can make things more complicated, but there are more than two examples.

Bits of countries changed hands in medieval times by marriage: Eleanor of Aquitaine comes to mind.

The British Empire wasn't entirely military conquest.

One problem seems to be finding the right people to buy the country from - just like bridges, there are plenty of people willing to sell you one!

England's problems after buying Scotland and Britain's after buying Afghanistan should be a warning.

Phil Kitching