Does anyone know if these used to be some kind of war posters or
something? http://www.liangdianup.com/index.htm
Were these sayings on these lighters actually used in war times?

I don't really know, but they are interesting. They reminded me at first of British wartime posters that are in the Imperial War Museum in London, but as the English is quite bad grammatically on the one with lots of text, they can't be exact replicas of anything from the UK and for that reason, I can't imagine them being very popular in a specialist memorabilia market over here, as authenticity is important. Actually, wouldn't English ones be more likely to reference Hitler or Germans if it's WWII? It might be interesting to find out who designed and produced them, and for what contemporary market, then you could find out what their original sources/inspiration were, though I'm guessing that they're made in China for sale in a US market. Do you think they might be derived from American wartime ephemera or other sources, going by the spelling of 'defense' and the phrase about 'your metal fighting the Japs'? Would war bonds have been an American thing?

Apologies for a reply full of more questions than answers, but good luck with it!

They definitely sound more American than British - apart from the wordy one that sounds more Chinese!

Here's one of the originals for you:
http://www.internationalposter.com/poster-details.aspx?id=USL15554

Well spotted, Timefortea! Other people's projects always sound really interesting when you're supposed to getting on with your own work... I seem to be the queen of procrastination today lol!