Frodo's visions at Amon Hen

[Legate of Amon Lanc]

I have never seen this as having anything to do with future. This is obviously and plainly the present.

Easterlings, Southrons, Corsairs etc. were obviously mustering for war at that time (for example Faramir says later that they've been doing that for some time lately), likewise, the Orcs in the Misty Mountains were already numerous again - starting from Moria where we surely have pretty good evidence of their continuous spread, but also elsewhere, as we can conclude. Half a century is enough time for them to breed again, and this is what I believe lies behind the mentioned attacks on the Beorning lands, possibly also combined with the powers from Dol Guldur being also on the move. I mean, in The Hobbit we hear that the Misty Mountain goblins had often been raiding villages of the Woodmen, later, once the Beornings had risen, it would have been the same.

There are proofs of the "renaissance" of the Orcs in the Misty Mountains as early as in the second chapter of FotR (emphasis mine):

Originally Posted by The Shadow of the Past

(...) The Dark Tower had been rebuilt, it was said. From there the power was spreading far and wide, and away far east and south there were wars and growing fear. Orcs were multiplying again in the mountains. Trolls were abroad, no longer dull-witted, but cunning and armed with dreadful weapons. (...)

So that leaves everything from Frodo's vision clearly explained, I believe, except for the "smoke rising on the borders of Lórien". But I really don't see a problem with that one, either. I have always been convinced that this was simply referring to the Orcs from Moria coming in the wake of the Fellowship. Yes, the three assaults from Dol Guldur upon Lórien came much later, but this smoke is just the result of the random raid by the Moria Orcs. Remember the Orcs who were pursuing the Fellowship from Moria? It is not unthinkable at all that the Orcs continued their attacks. In fact, it is implied (not clearly, but if you draw all the conclusions, it is pretty visible) that at least the Elves of Lórien were expecting more attacks, even after they got rid of (most of) the first group that was following the Fellowship. When the Fellowship was going with Haldir,

Originally Posted by Lothlórien

A marching host of Elves had come up silently: they were hastening toward the northern borders to guard against any attack from Moria; and they brought news, some of which Haldir reported. The marauding orcs had been waylaid and almost all destroyed; the remnant had fled westward towards the mountains, and were being pursued.

As you can see, this happens after the first group of Orcs has been destroyed, but yet the Elves are ready for more attacks from Moria. Revenge, perhaps? Especially with the few survivors from the first raid, maybe some of them brought the news to Moria and brought more of their warriors along?

And even much earlier, upon his first meeting with the Fellowship, Haldir implies that the Orcs (and Wolves) have been sniffing and messing around the borders of Lórien already for some time:

Originally Posted by Lothlórien

We have been keeping watch on the rivers, ever since we saw a great troop of Orcs going north toward Moria, along the skirts of the mountains, many days ago. Wolves are howling on the wood's borders. If you have indeed come from Moria, the peril cannot be far behind.

It seems like the atmosphere of conflict being just about to begin has been present there for some time, and after the Fellowship comes, it just falls upon Lórien at last. It isn't certainly as big as the later assaults from Dol Guldur, which are part of Sauron's war and are comparable to the attacks on Minas Tirith or Dale; it's probably something more akin to "border skirmishes". Nonetheless, enough to generate the smoke we are looking for