The cause of Imam Hussain (a) is not followed universally, but it is a universal cause. In fact, it is the only essentially universal cause - meant for all peoples of all nations at all times. It is unfortunate to see that some still carry an exclusive mentality regarding this.
You find them arguing against statements such as "Everyday is Ashura and everyday is Karbala.." Yes, this is not a narration from Ahl al-Bayt (a). It is actually inspired from the poetry of Sheikh Sāle'h al-Kawwāz al-'Hilli. But does this mean it is somehow false or incorrect?
They point out that the narrations from Ahl al-Bayt (a) have said 'there is no day like' the day of Imam Hussain (a), but who said this necessarily disproves or even contradicts the aforementioned poetry or the famous statement? It actually does not in any way, shape or form.
What is meant by the statement is not that there may be tragedies comparable with that of Imam Hussain (a), who we know is the divine representative; nor that wherever tragedies do occur, that land can then be equated with Karbala, which we know to be particularly sacred.
Rather, what the statement means is that the values, lessons and archetypes of Karbala are repetitive in history and the 'test' of supporting the divine representative is not yet over. What it means is that truth will always have those who stand by it and face tribulation for it.
What it means is that the struggle between virtue and evil, which has been ongoing since the beginning of time, has not stopped after the martyrdom of Hussain (a). Rather, the responsibility of human societies is now greater because Imam Hussain (a) set the ultimate example!
'Everyday is Ashura' in the sense that everyday people are upon the choice to stand for divine values and pay the price for that stance. 'Every land is Karbala' in the sense that justice and oppression can be found wrestling anywhere in the world. Can anyone deny such realities?
This is why we have narrations such as that mentioned by Sheikh al-'Hāeri in Ilzām al-Nāsib, v.2, p.243 - that upon Imam Mahdi's (aj) reappearance, he shall say: "O' people of the world, my grandfather Hussain (a) was martyred thirsty.." The Imam (aj) is speaking to the world!
The cause of Imam Hussain (a) is nothing but the cause of Islam; and the Qur'an is clear in showing that it addresses the humankind as a whole (7:158), (34:28), (4:79), (21:107), (25:1), and so on. We should not obstruct God's unlimited cause with our limited mentalities.
