It should perhaps be explained what an invasion really is so BB won't get confused again...

An invasion is a full scale military attack across the borders of a sovereign nation by infantry and mechanized and air forces of a foreign power, possibly with the aid of naval forces as well, if it is a seaborne invasion. It is done with the intention of conquering and occuping the recipient of the attack. It involves the direct use of massive lethal firepower by the above forces on the recipient. It does not cease when the recipient asks the invader to leave...

We have seen some invasions in the fairly recent past:

Iraq invaded Iran
Iraq invaded Kuwait
Israel invaded Lebanon (twice now)
A USA-led coalition invaded Iraq (twice now)
The USA invaded Panama
The USA invaded Grenada
A USA-led coalition invaded Afghanistan
China invaded Vietnam
Vietnam invaded Kampuchea

And there were others too. Iran has so far, however, invaded nobody.