The agressor.
Invading another country doesn't fit into categories of the kind implied by the question.
Invading means to send your military into the other country. You would then occupy that country by keeping your military there after you defeated it. If you move your people into that country with the intention on staying permanently, you would be colonizing it.
Japan
Army of Jericho.
Scotland isn't being invaded.
Apart form the fact that you have not said where they are invading, the best way is not to import them into a country where they are not indigenous in the first place.
they build wall to separate too country's from fitting and invading others country.
killer cells
Poland
Lebanon is a christian country but Muslims are invading us
Cambodia.
norway was crushed