1- It's possible
Unlike constructed languages like Volapük or Esperanto, Italian does not spin the minds of the world’s linguistic scholars. With more than 60 million speakers worldwide, it is always useful to learn.
2 - It is very European
Italian is only spoken in Europe. As a language it is rooted in European culture; it is the language of the renaissance, the time in which Europe rediscovered itself and when Italy did not exist as a country. It is the language of the awakening of pictorial art and music and the most direct descendant of Latin - indisputibly the longest standing language of Europe, its vocabulary influencing all other languages, studied and admired by all countries.
3 - It is not a dominant language
As opposed to languages such as English, French, Spanish, German or Russian, no-one is scared of Italian, nor do they worry that it will make their mother tongue extinct… except of course maybe Italians themselves!
4 - A beautiful and cultured language
Maybe due to its aforementioned association with music, it has never even occured to anyone in Europe to accuse Italian of being an ugly or coarse language; no-one can disagree with its musicality. An attractive reason to start learning any language !
5 - It is an easy language
Syntactically and morphologically: as opposed to French, Spanish, Russian or German, Italian grammar is considerably more logical and easy to learn. Its tenses are few and are extremely regular, its prepositions and articles are coherent, as is the logical sturcture of its genders and plurals. Furthermore, its Latin vocabulary has relatives throughout almost all European languages, especially the romance languages and English. Phonetically, it has just five vowels and uses the most common consonants of all European languages. Orally: each sound is clearly vocalised and it is rare and almost unnatural to merge syllables or even letters. Ortographically: faced with the systematic absurdity of English spelling and the whimsical and conservative ortography of French (not having a cyrillic alphabet!), Italian is possibly the most phonetically precise of all European languages.
This being the case, the only thing left to do is spread the message. Habemus Lingua! Or rather... Abbiamo Lingua!