I really don't see how Clanad's been wronged or is deserving of an apology (indeed, so far as I can tell, Clanad doesn't seem to feel he needs to be apologized to either). It's a perfectly valid question to ask why Obama's failure to visit the Normandy memorials are a good reason to criticise him as a president.
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Personally, I'm no great fan of Obama's - other than his symbolic value as a black president, it's hard to think of much that he has actually achieved other than Obamacare. And even though the principles of Obamacare seem noble enough, it's been mutated and changed so strongly by the politically-oriented compromises which often characterise American lawmaking that it may well turn out a bureaucratic nightmare.
Having said that, his challenger looked even more uninspiring - even actively dangerous. I don't think that the USA is headed for 4 years of hope, change or excitement - if I were to make any guesses, I would guess that the USA is in for 4 years of gridlock and political immobility very similar to the previous 4. But if I were a US citizen, I think I'd still consider that preferable to the disastrous alternative represented by Romney.