While I agree on the Mordin statement, this is rather short sighted imo. (Also topic of several topics before)
Isn't it the other way around? Going for the easy solution now without concern for the implications of its implementatioon on the future is the definition of "shortighted". Mordin is the one being shortsighted, not my Shepard.
Disregarding meta-Knowledge
I had no meta-knowledge of the matter at the time I was playing the game and my opinion then was the same as I presented now. I was ready to decieve the Krogans come hell or high water based solely on what I knew by the time I arrived in Tuchanka.
At that point Shepard only knows that the war could take centuries.
False, as shown both in-game and via war data from Earth. Liara has projected the spacefaring galaxy as a whole may hold out for one century at the best before total defeat. (long before this of course several species will be gone)
It is also irrelevant how many centuries, or even decades the war would last. What Shepard knows is that right now the casualty rate on Earth stands at 7 million per week (check the "London Invaded" trailer) and that is before deaths due to famine, disease and general infrastructure failure begin to add to it. This means total decimation of its 11,400,000,000 population will happen in less than 4.5 solar years (unless the Reapers decide to take a little breather). Fully, irredemable civilizational and cultural collapse will of course happen well before that.
(This is why you/the Turians want the Krogan in the first place.)
No. The Turians want Krogan boots-on-the-ground in Palaven for ground operations to help them prevent getting their asses kicked because in ME land-based infantry is magically a countermeasure to orbital assaults. We want Turian space fleets to support our own operations on Earth so the same doesn't happen here (human infantry apparently does not have the same anti-space-fleet magical powers of Krogans and Turians...because reasons). Krogans are not deployed in numbers on Earth until the final Crucible joint operation, and that only happens because the Citadel has left the Nebula and come to Sol system, which no one saw coming. Even then, the Krogans warriors making landfall on Terra are not newborns issuing from genophage cure, but adult pre-existing warriors.
The Demographics of the Krogan have zero effect on the course of the war, and the operational plan expected as much.
If this kind of war, and with the Krogan fully commited to it, they will simply run out in a few years -If not cured- because there are not enough newborns.
I don't want to sound obtuse or confrontational, but it would really help if people opinating about Mass Effect actually bothered to play the game, or if they did, make an effort to remember what its setting presented us with.
The human war strategy in the war against the reapers on ME3 is never organized assuming years of warfare. There is the Crucible and you need some months to build the thing , so you have to:
a) hold out until then
deploy the darn thing with as much of a massive fleet as you can, preferably with as many species as possible because the Reapers are sure to try and stop it
and
c) No one projected large combined force operations on Terra of the likes of Hammer until the Citadel drops by the Sol system. It was half ass-pull half improvisation. A desperate gambit where the biggest combined fleet of the cycle was mostly a ruse to deploy some ground mook reinforcements and buy them enough time for their shinning space elevator operation and the copulation of Crucyble + Citadel.
If the Turians didn't need the Krogan on Palaven and had just given Humanity fleet assistance from day one the whole Tuchanka arc would not have happened. The Genophage cure is a political carrot to indirectly obtain Turian spaceships to buy our humanoid Terran asses enough time, it has nothing to do with the war effort directly and its demographic effects on Krogan are going to have zero effect on the wartime operations as planned. Everyone knows this from the beggining. The only reason its the genophage is the issue is because whoever is running the Krogan circus wants its. He could have asked for one megaton of Eezo, or something else entirely. And the reason the genophage is getting cured right now is because the blackmailing bastard wants it now. Not because its demographic effects years from now are somehow part of the war plans.
If this kind of war, and with the Krogan fully commited to it, they will simply run out in a few years -If not cured- because there are not enough newborns.
Irrelevant and false. Earth will be depopulated well before future Krogan newborns mature to be ground forces. You aren't giving the Genophage cure to get the Krogan warriors of the future for a long. protacted war of attrition. You exchanging it for the support of the millions of Krogan warriors existing right now, and the goal is not to defeat the Reapers in direct confrontation but to "hold the line" for a few months so that:
1) Palaven doesn't go bye-bye presently
2) The Turian armadas assist with preventing that (1) does not happen to earth
3) This status belli is maintaned as much as possible until the Mega Space McGuffi...er i mean the Catalyst is built and can be deployed.
I can't remember the number of times I heard the line "We cannot defeat the reapers in direct confrontation." while playing the game. What are Krogan going to be used for? For direct confrontation agaist reapers. Wait...are these people stupid? No. The reptiles are going to be used as cannon fodder to hold the line temporarily for an ally who will then provide us fleet support so we may hold the line in our own turf as much as posible until the crucible is complete.
With the Krogan cured, there is a small chance to hold out that long and eventually defeat the Reapers.
Without the cure you have no Krogan support after a few years and are that much closer to defeat.
What the Krogan could do after an eventual victory over the Reapers is something else, but personally I'd rather get headbutted into stoneage than turned into an DNA- smoothie.
I am going to repeat myself, again. Every human on Earth will be dead or huskified in less time than it takes them future Krogan newborns to become viable warriors. Repeat after me: Krogan demographics with genophage cure have nothing to do with the fate of the Earth in ME3 or the war plans of the alliance and its allies. There is no "hold out long", there is only "Hold out NOW and pray the Catalyst works" in their plans.
What the Krogan could do after an eventual victory over the Reapers is something else, but personally I'd rather get headbutted into stoneage than turned into an DNA- smoothie.
Except that unlike the reapers, we do not have a space mcguffin Catalyst that we believe can can defeat the Krogan hordes in one fell swoop once they get uppity. Ergo from the point of view of the Alliance and any war analysts in their ranks who aren't fully retarded, while the Reapers are a clear and present danger right now, Krogan hordes will actually be more dangerous and harder to deal with in the near future.
You won't get a chance to be headbutted to the stone age because an eventual victory over the reapers means the population of Earth has already been turned into DNA- smoothie...or huskified...or got a red ocular reaper laser up its behind..or was lost to starvation/disease/exposure/etc. Heck, that has already happened to the Batarians and the Elcor even before the ME3 game is over.
For Earth (and Palaven, and Thessia later in the game) there is no place for terms like "eventually", "protracted" or "long-term" in this war. You either stop the reapers via McGuffin within a few months at most, Krogan baby boom irrelevant, or YOU LOSE! Game over man, game over! Go directly to Jail. Do not pass "Go!", Do not collect $100. Period, Paragraph. End of situational premisse.
Remember, I didn't write the darn thing, and I am not saying I like it or even defending it. I think the premisse and narrative are contrived, illogical, non-sensical and rail-roading from the opening sequence onwards, and they let you know everything is hinging on a Deux Ex Machina from the moment you finish the Mars Base mission and that there's no other way. I am just laying it out as it is then pointing out, correctly, that according to the bullsh*t the very setting has established when the option is given to you, curing the Genophage when you don't have to is not only nonsensical, it is downright counterproductive if you win the war against the reapers...which is the darn point of the game in the first place, innit? So why risk another genocidial war in the near future when you don't have to?
Now, if you want to give Krogan the Genophage cure because you like them, or because your personal morals and ethics dictate you should do so, that's another matter and feel free to do so. I have zero problems with those choices or the logical behind them. Just don't try to pass them off as the correct and sensible one for the sake of the continued existence and safety of Terra given what Shepard knows at the time the option is given because it objectively and demonstrably isn't.
And of course, if this was a real-life situation I (meaning me vargr1105, not fictional Shepard) would shoot you in the back without hesitation to prevent you from doing it, and afterwards go back to my crib and sleep guilt-free like a baby with full knowledge that, if there is a God, he would be smiling down upon me. 
I mean, if every female actually can give birth to dozens or hundreds little Krogys every time, and can do this repeatedly in a relatively short period,
the Krogan will be able to multiply faster than WH40K's Orks...
In-game cannon tells us that:
1) Krogan females cured from the genophage can have 1,000 offspring per year normally.
2) There are a billion fertile females in Tuchanka.
You do the math...
And while we are at it who the flying f**k thought it was a good idea to have an 1000% fertility rate increase amidst a galactic war? Yeah...all those millions, upon millions, upon millins of babies are going to have zero detrimental effect on resources and infrastructure both during the war and during reconstruction if the reapers are beaten.
I will point it out again: 1000% fertility rate increase
Anyone who thinks the Krogan Rebellions 2.0 aren't going to happen, even if just due to sheer population pressure and resource exausthion...is an idiot (i.e. a person who has bad ideas).