Tigerlily, you're correct in the stated casus belli, but not in it's strategic importance.
An island in the middle of nowhere which most people, apart from some WW1 officianados, had heard of didn't figure highly in the national conciousness.
I hate Thatcher with a passion, but, even I don't think she was so cynical as to want a khaki election in order to maintain her power.
If you look it up, our presence in the Falklands gives us certain rights in the region to drill for oil.
Modeller I think there was an Argentine garrison on the island before we arrived, which we promptly routed, a long long time ago though, the facts on the ground (makes us sound a bit like Israel) make a hand over quite untenable, and that's before you exclude the war.