Upon exiting from the tevah, God declares the following to Noach:
“All living things that roam upon the earth are yours to eat; similar to the vegetation which I [previously] allowed you to eat” (9:3)
Why does God allow humankind to eat meat specifically now? Practically, at this juncture of a new world’s inception, it is probably one of the worst times to proclaim open season on the animal kingdom; but more pedagogically, what are we supposed to learn from God’s decision particularly at this point to allow humankind to eat from the animals whereas previously, only eating from the world’s vegetation was permitted?
This new Divine declaration is found at the conclusion of God’s statements which immediately followed Noach’s disembarking from the tevah and subsequent bringing of korbanot. So, to fully answer this question, we first must understand all the events leading up to the moment of which this statement is a consequence.
Originally, God commands Noach to bring (תביא) with him two of every species (male and female) into the tevah in order to – “להחיות” – sustain animal life (6:18-20). He then commands Noach to also take (תקח) seven animals from each of all the species of tehorah animals, (as opposed to only two of the non-tehorah animals), and seven of all species of birds (presumably, tahor and non-tahor) (7: 2-3). The reason God gives for this command is “לחיות זרע על פני כל הארץ” – to produce life over the land (i.e. not merely to sustain it as He had commanded previously regarding the bringing of the pairs of each animal species).
In other words, when it comes to facilitating a renewal (“לחיות”) of animal life in the new world to come – so that these specific species will represent a new beginning, born from the previous world’s animals – Noach was commanded to significantly and actively take (ל.ק.ח) (a word also used in the context of acquiring/buying); however, for the purpose of merely sustaining animal life (“להחיות”) – in essence continuing these species from the old world in the new world – he is commanded to merely bring (ב.ו.א.) (i.e. collect or gather). What we can now understand is that God required Noach to actively and significantly participate in the renewal of the new world’s animal kingdom; but, only to merely gather the animals that represented the continuation of the animal kingdom.
And when the Torah reports the very day these animal boarded the tevah (ibid 8-9) it states that ‘from the tahor animals and the non-tahor animals, the birds and all the creepy-crawlers, two by two they came (“באו”) to Noach’. This is exactly the actualization of the first command God gave to Noach: to bring two of every species of animals. But, then the rain begins and the world is destroyed – so what happened to fulfilling God’s second command!? Strangely, upon exiting the tevah (8:20), we are told that Noach takes from all the tahor animals and birds to bring as korbanot, but there’s no way there were only two of those animals, because otherwise, upon bringing them as korbanot, these species would have ceased to exist – so there must have been the required seven! So when did the fulfillment of this second command – which was obviously completed – occur? We would have to assume that even after the two-by-two animals came to the tevah, Noach must have then gone and collected the additional five of each tahor species (and five of all bird species) to round out the Divinely obligated seven. Which is a perfect expression of the required “תקח”! He actively and significantly made it happen (where it wouldn’t have happened otherwise!). Noach, representing the new humankind on the earth, was specifically charged with actively facilitating the future active ‘recreation’ of the animal kingdom in the new world, and Noach answered that call.
When Noach finally exits the tevah, he immediately brings korbanot from the tahor animals and tahor birds, the very animals which Noach actively ‘took’ in order to represent his direct involvement in the creation of the new world’s species! And upon smelling the scent of these korbanot, God promises to never again curse the ground and smite all living things (8:20-21). Why does Noach’s action inspire God to proclaim such dramatic and positive resolutions? By bringing korbanot from these specifically “brought” animals – the very animals which Noach actively designated as the renewal of animal life in the new world – Noach significantly and purposefully expressed a new specific relationship between the living beings of the world: people using the animal kingdom to allow the humans’ uniqueness of צלם אלוקים (which animals do not possess) to be employed positively, heightened productively, and ‘distinguished’ in all senses of the world. And because of this symbolically significant voluntarily chosen act, God is ready to never destroy such a world again.
And now we return to our original issue: the ‘strange’ permitting of eating from the animal kingdom. In Breishit 1:28-30, God commanded Adam to be fruitful and multiply and populate the world (“פרו ורבו ומלאו את הארץ”); He also commanded them to conquer it and establish authority over the animal kingdom. However, after God commands Noach with the same responsibility to be fruitful, multiply and populate the world, using the same exact words, (“פרו ורבו ומלאו את הארץ”), He then says, “and your awe and terror shall be upon the animals of the land and the birds of the sky…”. This time around, the ‘authority’ that humans are commanded to impose upon the animal kingdom is much greater, much graver and ‘scarier’. Humans now are not merely to play a supervisory, foreman-esque type role but rather are charged with imposing a deep awe and fear over the animal kingdom. And this change reflects the exact significance Noach actualized when he brought his korbanot from the tahor animals and birds. He created a distinct separation between the human and animal world which was essential to these worlds’ continued survival; and God then responds in kind, enabling that eternal existence by reworking the reality on the ground, literally. If the world will only survive because humans use the animals within it to elevate the entire world – and the humans are ready to actively accept that responsibility (as proven by Noach’s bringing of the korbanot) – then God will create a system that sustains that formula. And how is this new system manifest? Previously, in Gan Eden, when describing what was available for consumption, God instructed that all vegetation (“את כל ירק עשב”) was available for human beings to eat just like it was for the rest of the animal kingdom. However, now, in establishing the new world upon this new system, God tells Noach and his family that [now] all the animals are now also available for them to eat “just like the vegetation (“כירק עשב”) I have given them to you to eat” (9:3))! Originally, the guidelines of what could and couldn’t be eaten equated the humans and animals of the world; now in this ‘new world’, the very same category of guidelines serves to separate the two.
 Interestingly, when the actual day finally arrives the non-tahor animals come (באו) to Noach; so his charge to ‘תביא’ (as opposed to the second command of the active ‘תקח’) is rendered an even more passive action.
 This fits with the midrash that explains that the animals were also similarly punished with the destruction of the world because they sinned just as the humans of the world did; there was no distinction between the living beings of the world in sin.