Difference between っての名詞　and る名詞


In the grammar explanation for なりに on
[japanesetest4you.com](https://japanesetest4you.com/flashcard/learn-
jlpt-n1-grammar-%E3%81%AA%E3%82%8A%E3%81%AB%E3%81%AA%E3%82%8A%E3%81%AE-nari-
ninari-no/), I ran into the following sentence:

私には私なりの理由があっての事だったんです。

I am curious about one part in particular:

があっての

Is this any different than がある? I know の makes it so that あって describes the
following noun instead of the following verb, but why not just use がある instead
— which already modifies a noun by default?

The one reason I can think of for using があっての is in conversation when the
speaker is not yet sure what they will say next and needs to tie the って to a
noun. But I am unsure if this would be the main for using or if this would
work with every verb.




あっての emphasizes the prior phrase as a reason, without which the following
phrase could not be. Please see
[here](https://www.mlcjapanese.co.jp/n1_04_15.html) for other examples

がある would not make much sense here as a modifier of こと。You could say
私には私なりの理由があったんです, but it is not as strong an utterance.




あっての emphasizes the prior phrase as a reason, without which the following
phrase could not be. Please see
[here](https://www.mlcjapanese.co.jp/n1_04_15.html) for other examples

がある would not make much sense here as a modifier of こと。You could say
私には私なりの理由があったんです, but it is not as strong an utterance.

