At the beginning of 'Endgame', the borg had exceptionally little interest in the federation/humans:
The borg actually didn't bother assimilating a starfleet ship full of humans! An easy target, too - a single ship, surrounded by dozens of borg cubes.
"Dark Frontier" established that the Queen deliberately left Voyager unassimilated because she had intended to use Seven of Nine as a sleeper agent to study the humans/Federation and learn how to overcome their unusual ability to resist assimilation. Don't forget that the Borg had already tried to assimilate the Federation twice at that point, first in "The Best of Both Worlds," then in "First Contact." The Borg were quite obviously interested in the Federation long before "Endgame."
But the Federation was just one of the many civilizations galaxy-wide that the Borg was battling. We may not have seen them onscreen, but given the sheer immensity of the galaxy and the substantial percentage of it occupied by the Borg, it's inevitable that the UFP was just one of many priorities the Borg had, and since it was very far away from the core of Borg space -- aside from Voyager, which was just one measly ship -- the Collective could afford to keep it fairly low on its priority list while it dealt with more pressing concerns. But "Endgame" pushed the Federation to the top of their priority list.
I agree with this assessment.
One thing - being low on the borg's priority list is a good thing, when you're practically defenceless against even a relatively small scale borg attack.
The comparison is not accurate on one point:"Sleeping?" Not even close. The Borg were waging an active, aggressive campaign of genocide across the entire galaxy. They weren't "sleeping" any more than the Nazis were sleeping in the late 1930s when they swept across Europe. What Janeway did was analogous to what many Americans wanted to do -- take direct action against a global-scale threat rather than just passively sitting by because it hadn't directly focused on them yet. And those people who wanted to intervene turned out to be right. It was irresponsible to sit by and allow the Nazis and the Japanese to build rapacious empires at others' expense. The right thing to do in the long run was to take action to stop them. True, those nations that fought the Nazis and Japanese suffered great losses by choosing to stand against them, but the losses to the whole world would've been far more profound if they hadn't.Janeway's actions caused this massive shift in the borg's priorities.
Irresponsibly, she poked a sleeping giant in the eye.
Janeway is not the equivalent of an United States citizen - a nation which had the means to match nazi Germany's power.
As said in my previous post, Janeway is the equivalent of a member of a primitive amazonian tribe, armed with bows and spears. Such a tribe - even allied with other similar tribes - taking action against nazi Germany would only ever result in its extinction.
No chance of victory or survival whatsoever - as 'Destiny' showed.