I've been reading lately about the Lancastrians and the Wars of the Roses, and everything I've read agrees that Margaret of Anjou was a disastrous choice of wife for Henry VI. Furthermore, it seems to have been obvious at the time that it was a bad idea, to the point that the terms of the marriage (where Henry gave away two French provinces instead of getting some as a dowry) were kept secret because they would be so unpopular.

Nobody I've read has explained what the upside was. If the marriage was such a terrible idea for the English, why did it happen? Who benefited?

Was it a bid for permanent peace with France that failed?

Was it a power grab on the part of some English nobles, hoping to rule Henry through a queen that owed them her position?

Was it an attempt to give the monarchy some backbone by giving the inert Henry a strong-willed queen?

Was Henry just in love?