Well, our country didn't exist pre-1947, but we're arguing semantics now. Still, it's kindof bonkers to define the border of a fairly young "nation" over a period of 3000years. If you do that, then you need to consider the Mughal campaigns in Central Asia as they attacked Samarkhamd (Persia) as well as Kandahar (also persian held at the time). Or do you not consider them Indian?
OK then, consider that the Chola empire conquered sections of South East Asia. But perhaps you dismiss these conquests as exaggerations? (note that there is overwhelming evidence that atleast ports were raided even if there was no lasting presence -- it's still an "attack")
But if we are going to be pedantic, even post-Independence India declared war on Portugal and is considered the aggressor state when it "invaded" Goa: http://en.wikipedia.org/wiki/Invasion_of_Goa