These advertisements from National Geographic were taken from a 1918 edition. This was after the US involvement in the "Great War". The tone of the advertisements seem to be more about the war effort and are quite propagandistic. You can sense the priority of this conflict in these advertisements.

I am contrasting these with the April 1945 advertisements. Like the 1945 items, the advertisements here are made towards the end of the war. While the end of the war was probably not as clear when these were created as those in 45, you notice a slight difference in tone of the 45 advertisements. I do not collect National Geographics, so I only have a few to compare, but the 1967 edition I have has no mention of the current conflict at all.

That Monstrous Thing Called Kultur Providing the Sinews of War
That Monstrous Thing Called Kultur
There's a fester spot on this fair world--a spot that has spread from Berlin until it has poisoned all of Germany. And there's just one cure--the knife. The poison cannot be dammed up, it must be cut out else the monstrous thing called Kultur will fasten its hideous self on all the world.
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Providing the Sinews of War
The Hercules Powder company provides the sinews of war that will ultimately bring us victory.
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We Must "Follow-Up" "THE EYES OF THE NAVY"
We Must "Follow-Up"
Then let us at home turn from our flag waving and consider how necessary we are, how useful we must be. Those who go to fight cannot hope to win by naked bravery and we cannot hope to win unless every individual at home does all he can. We must have no Gallipoli.
(Anzac stands for Australian and New Zealand Army Corps)
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The Assistant Secretary of the Navy, Franklin D. Roosevelt calls for your Binoculars to spot German submarines.
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Ivory Soap - 99 44/100 % Pure Enlist Your Lens in the Air Service
Ivory Soap - 99 44/100 % Pure
Ivory Soap is, in fact, the very joy of living to Our Boys when they are relieved from the from lines for rest, recreation, clean clothes and a bath.
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Enlist Your Lens in the Air Service
I find it interesting that many of the lenses that they are asking for were produced in Germany.
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