It's a fact that Messi has performed at a substantially lower level whenever he plays for Argentina. Fact 2, international competitons have always carried more weight than club ball.
your Fact 2 statement is a load of bollocks! Whose FACT is this?!
World soccer has been on the decline for years and there's a huge difference between club football and international football in terms of tactics, play style etc etc.
Are you really denying that the World Cup has always been the most prestigious tournament? WTF do people talk about when discussing Pele and Maradona? Who even remembers how many league titles they won? Even Zidane in the modern era, earned his lofty status largely through what he did at the World Cup.
If international ball no longer matters, then why is England so upset about its "Golden Generation"? Geurrard, Lampard, Beckham, etc. should still be considered legends, right, since they accomplished so much in club football?
For sure, the quality of football is higher at the top professional levels but that does not mean club football is more prestigious than international football.
this makes zero sense - so no one is a super star unless they "do it" on a world stage? What about reverse cases like Milan Baros? He's an immense international player but he was a total and utter scrub at club level. What about world class highly decorated players like Giggs who are by birth in a poor international team (though Giggs did qualify to be in the England team he was pursuaded at a young age to play for Wales (also qualified to play for)).
That's not what I mean. A player needs to be great at club and at international to be considered a Superstar. I don't know why you're getting so upset over this. Basically the same criticisms were made of Frank Lampard and Messi defenders, including yourself, had no problems with it. If international performance doesn't matter that much, why aren't we putting Lampard on the same level as Messi as one of the greatest of all time?
I don't know what else you can ask. It seems like you need him to single handedly win the world cup for him to gain the reputation he already rightly holds 
Score some goals? I don't know how the top scorer in the world scoring 0 goals in 5 games (2010) and 0 again in Copa America can be classified as anything other than underacheiving. Even fatass Ronaldo was able to score 3 in his last World Cup.
