Then they need to lobby for the station's removal if that is indeed the will of the argentine people however that is an internal issue within the people and the government of Argentina.
The fact remains that the station was put there legally between the two government of these two countries.
This is not very different than the mistral ships between Russian and France. It was purchase legally but due to both interl and external pressure French reneged but they did it legally as well and had to compensate for breaching of contract.
You still do not understand, in the history of Latin America, Europe and the US have a lot of saying, why? consider that around 50% of the whole population of Latin America is European in origin and the rest is a mixture of native Americans, Europeans and Africans, these populations are mostly Portuguese and Spanish but there is a lot of Italians in countries like Uruguay and Argentina, these populations are very loyal to Europe and the US, however recently Brazil wants to become the core nation of South America.
Argentina has been rejected by NATO and the IMF, this made Argentina strike the deal with China, plus the irrefutable fact Chinese investment has been promised to Argentina, Argentina will respect the deal as long as a politician like
Cristina Elisabet Fernández de Kirchner is in power, however if some sectors in Argentina think China is not giving so many advantages in terms of Industry, investment will yield to American and European pressure.
And i can assure you something Europe and the US will do whatever they can to eject the Chinese base from South America and they will do it via all the politicians who want better relations with the US and Europe.
Believe me Europe and the US will not rest until they can make Argentina reconsider.
Argentina will keep the base as long as it has a lot of benefits and it helps Argentina as a bargain tool with the US and Europe to easy pressure from England and even as a bargain tool to regain the Malvinas/Falklands.
And that is the whole reason China is there, Argentina is using China as a bargaining tool with the West