The irony simply comes from the "little green men" i.e. the Russian "volunteers" sent in Crimea/East Ukraine who were suspiciously well equipped and organized,

The irony simply comes from the "little green men" i.e. the Russian "volunteers" sent in Crimea/East Ukraine who were suspiciously well equipped and organized, almost like they were Russian Army military units in all but names. As for the "country" sending fighters, in this instance, it's miss-representative. These are legit volunteers acting on there own initiatives outside of any government's call to arm, a bit like the International Brigades of the Spanish Civil war. Lastly, Putin is a gambler, but not an idiot nor a lunatic wanting to end the world nor a leader in a desperate situation. He made a gamble in Ukraine because he knew he could somewhat get away with it (even if things are not exactly going according to plan). He will not start a global/nuclear conflict over a silly matter like few hundreds foreign combatants acting on their own initiative, which doesn't mean he will not posture against it.