Many believe Kluivert deserved a place in the Oranje squad given his form with the Cherries last season.
But Iraola told the Daily Echo: “You realise now how difficult it is to play for your national team, especially with some countries.
“You see the French players that are not going to be involved and that is a hell of a team.
“Or the Dutch players, or German players. You say it is impossible he is not involved, but for sure there are reasons.
“Every national team coach is thinking ‘we are going to play this way, I need this profile, this other profile and probably it is a shame, but I cannot fit everyone’.
“With Justin, it is a little bit the same.
“He finished the season very strong. He has made the numbers.
“He is in a good place. But it is strong opposition.”