roundさん、こんにちは。またお願いします。

Canal street was beaming with support and energy and I'm glad that I could be apart of this event as an ally. I remember cheering on a crowd of people and then someone hugged me and said “I love you so much. I feel like ...

上記英文中の I'm glad that I could be apart of this event as an ally.の [could] は直説法だと思います。I'm glad that I was apart of this event as an ally. と書き換えても、意味に大きな違いはないと思います。

I'm glad that I could have been a part of this election," Spector said. Spector said she still respects Dole and all that he has accomplished. "He achieved as much as he could in his lifetime. I respect him as a person, I just think that his time has ...

上記英文中の I'm glad that I could have been a aprt of this election の[could] は仮定法なのでしょうか？　上記英文を [could] を使わずに書き換えた場合、 I'm glad that I was a part of this election となるのなら、[could] は仮定法だと思うのですが、この考えは正しいでしょうか？　そうである場合、この [could] は昔習った感情の[should] と同じような物なのでしょうか？