Because it, like history in general, is far more complicated than that waving of cardboard cutouts suggests. And it’s inaccurate. The problem was not that Clement didn’t recognize Henry’s marriage to Anne. He had, in fact, authorized it, given that the marriage to Catherine was determined to be invalid. It was the failure of Henry’s request for that decree of nullity that caused the problems. What Henry was trying to achieve; a decree of nullity, with respect to his marriage to Catherine, based, in his causa, on the Levitical prohibition (not his strongest case)), and why, were commonplace events in the day. The entire system of matrimonial impediments, dispensations and decrees of nullity were set up, and steadily refined, to permit two things simultaneously: maintaining the Church’s control of matrimony as a sacrament, and permiting the making and breaking of dynastic marriages, as real-politic required. It grew to be a baroque and complicated process, so much so that Trent, Session XXIV, took it in hand and reformed it a little.
The best tale of just what was going on is found in J. J. Scarisbrick’s bio of Hank, HENRY VIII, which I recommend to anyone wanting the details. It’s not pro-Henry, it’s pro-history, and Scarisbrick is RC.
If there are any particular points that might be raised, Horny Hank and his hormones, and the problems he ran into, have been a long-time hobby of mine. Might could help.
GKC