Why learn French
French is the only language besides English that is spoken on every continent, and it is one of the few whose number of speakers is rising quickly rather than slowly. Most of that growth is in Africa, which is where the language is heading.
A working language, not a courtesy
It is an official language in twenty-nine countries and a working language of the United Nations, the European Union, the International Olympic Committee, the Red Cross and much of international law. In those rooms it is not decoration - it is the second language business is actually done in.
A third of English, for free
Roughly a third of English vocabulary arrived from French, so you begin with thousands of words already half-known - nation, important, possible, restaurant. No other language gives an English speaker that much for free on the first day.
It is worth points in Canada
Canada makes it worth money. French is one of the two official languages, Quebec runs almost entirely in it, and the federal immigration system awards extra points for French ability - in some streams enough to change whether an application succeeds.
A door into Spanish and Italian
And it is a door into the other Romance languages. Once French is in place, Spanish and Italian cost a fraction of what they would have cost first - the grammar is built on the same frame, and most of the vocabulary rhymes.