Using Arnold J. Toynbee’s concept of challenge-and-response (though very likely not entirely in a sense he would consider canonical), I am seriously puzzled at the discrepancies between the outcomes ending the First respectively Second Ages – or for that matter the first onslaught of the Valar upon Melkor, involving “personal” actions of the former against the latter, around the time of the awakening of the Elves.
At the end of the First Age (of the sun and moon, post the Two Trees), there is a direct confrontation between the Valar (Manwë’s herald Eonwë is named) and forces sent from Valinor with Melkor / Morgoth and his forces. Takes fifty (?) years in total, and Beleriand is wiped out – sinks below the seas. Even assuming that Morgoth by then, having dissipated his immense but quite bluntly finite power so massively (the concept behind all of Arda being “Morgoth’s Ring” compared to Sauron’s pathetic trinket) that he had shrunk in remaining native power below what Sauron still had left, he still controlled massive military resources – releasing Ancalagon the Black at the end, who (very unrealistically, Eonwë would have tied the critter into sailor’s knots with ease) was only defeated by the intercession of Eärendil, wearing his Silmaril, and his hallowed ship. Inconsistent, I would say.
Then Ar-Pharazôn and his navy show up on the shores of Valinor. Excuse me, it would have taken Eonwë's expeditionary force of the First Age about an afternoon to shred A-P’s invasion force. And never mind that an annoyed burp by Ossë would have annihilated A-P’s entire navy about a furlong out of harbor by some combination of hurricane and tsunami. OK, the Valar were not allowed to take action against the Eruhini in this manner, apparently. But why the §$%&ß@µ€ didn’t that jerk Eru, for whom I more and more imagine him having PJ’s face, vaporize Melkor, Sauron, Ungoliant, Balrogs and whatnot in punishment, vaguely resembling Zeus’s lightning bolts?
The Valar laid down their rule over Arda and appealed to Eru to take care of this situation for which he had not given them (the good guys) the necessary “clearance” against the bad guys, who apparently had no limitations imposed on them. The result (I exaggerate slightly) is like the use of a big thermonuclear weapon (aka H-bomb) compared to the use of a hand grenade. I have been annoyed at the Valar for ages because of what I have viewed as their wimpy and naïve treatment of Melkor and his cronies (and Manwë is in the pole position without any competition – cripes, even Tulkas got it about Malkor!!!) But the blame lands squarely at the doorstep of the ultimate moron Eru who could use some practical advice on (re-) socializing deficient “patients” from – lemme think - Cesar Millan, perhaps?