Why is 'dukkha' included in one of the three marks of existence?

In this link and this link the Buddha says that "there is stress" (or suffering or whatever your preferred translation of dukkha is). The Buddha does not say that suffering (dukkha) is inherent or an innate characteristic of existence. According to the Second Noble Truth, this dukkha is caused by desire or craving. So dukkha has a cause. That cause can be removed. It's not that existence is made up of dukkha. I understand Annicca (impermanence) and Annatta (not-self) can be said to be 'marks of existence' i.e. existence is characterized by them. But I don't understand how dukkha is a mark of existence. It is true that under certain circumstances humans feel dukkha but there is also joy, happiness, love etc. Dukkha is not a permanent building block of human existence. Annicca and Annata are permanent or basic building blocks. So my question is, why is dukkha said to be a 'mark' of samsaric realm or material existence?