Hello there!
Your answer would be Globalization.
The reason why "Globalization" would be the correct answer is because that is what it's called when countries have a closer "connection" with each other. Globalization is very good when countries get together have give each other deals in things like imports, trades, communication, etc. It's actually beneficial when a country could have connections with an international country because they both have different things, and they could offer each other stuff that the other probably doesn't have. There are also many downfalls of Globalization that could potentially start war.