The bullet points are pretty much trash with a severe modern political inclination to them. I'll run through them in the moment but should add that I haven't clicked through to the link since I'd rather not give more traffic to someone who posts this kind of stuff. If you have other questions from what this guy wrote I can try and answer them as well, though. I'm also switching the bullets to numbers for easy of keeping track.

1. I have no idea where he's getting this 'delayed response' crap from. I presume he means 'overdue' but I won't get into that since it's equally pointless. I'm not going to address his specific points here, doing so would go on forever, but I do want to address to major misconceptions he appears to have. Firstly, his description of life under Islam is seriously pot-kettle when compared to Europe at the same time. Islamic rulers were not always kind to their Jewish or Christian subjects but they were certainly no worse than their Christian counterparts in Europe, and arguably better in general. This was the Middle Ages people, it wasn't nice. Secondly, Islam was not a monolith. Not only was it racially divided up among Turks, Arabs, Kurds and other smaller groups it did not have a unified ruler. There was an active conflict going on between the Fatimid and Abbasid Caliphs who were each based on one side of Syria while the North Africans largely ignored the Muslims to their east. The Crusades are often painted as a Christian vs. Muslim event but this vastly oversimplifies the complexities that existed in those two religions.

2. Defensive Action is some seriously modern war terminology that has no place in discussions of medieval war. The First Crusade was called for by Urban II at the Council of Clermont in 1095 though.

3. Ugh, so much wrong here, where to start? The primary cause of the First Crusade is somewhat debated by historians. While Urban II's speech at Clermont certainly kicked it off we're not sure why he did that. Unfortunately the records of Urban II's pontificate were lost to fire before modern times so we don't know much about him or his reasoning. The most common narrative is that Emperor Alexios I of Byzantium asked for aid from European Christians to help take Anatolia back from the Turks (Byzantium had lost it in 1071 in the wake of their defeat at Manzikert). Some historians have argued that he just wanted mercenaries but instead got the Crusaders instead. Others have pointed to sources related to Raymond St. Gilles, an important Crusader, that suggest that he knew about the Crusade before Alexios' request could have reached Europe. This also feeds into the issue of we're not sure if Jerusalem was always the intended target of the First Crusade or if things just developed that way as they went. Records are a little unclear. Other problem I have with this is when the Crusades are grouped together as if they share a unified cause. Each of the Crusades had a slightly different purpose when it was called. The first was discussed above while the second was a response to the fall of Edessa and the third was in response to the fall of Jerusalem and it gets complicated from there. This is to say nothing of the fact that numbering the Crusades is a largely historical pursuit and individuals went on Crusade between 'official' crusades with decent frequency.

4. Unsurprisingly as with all things Crusade related there is some scholarly debate here about motivations of Crusaders. One thing we can all agree on, I think anyway, is that they were not universal. Some Crusaders certainly went with the goal of taking Jerusalem for Christianity while others (see Bohemond) were interested in territory primarily and Jerusalem secondarily. One thing that has been shown pretty well is that Crusading was not a hugely profitable business. Going on Crusade was very expensive with little likely monetary profit received in exchange. On the other hand, going on Crusade was a great boost to your prestige and reputation so it could certainly help your image, especially if you were a king. I probably don't need to point out that the wording of his point here is super racist as well. Jerusalem is a holy city for Islam as well, Mohammed ascended to heaven there, so they have religious reasons for wanting the city as well. It is a little ironic to describe the Muslim invasion as 'brutal' given that the Crusaders reportedly butchered everyone in Jerusalem when they took it....

5. I actually don't know what exactly he's arguing here, but colonized is another one of those words you probably should avoid when talking about medieval history. I think he's referring to the oath the Crusaders swore to return all conquered lands that used to be Byzantine back to Byzantine rule and then the political mess that followed but it's certainly an odd way to do it. If that is what he's referencing he seems to be throwing some serious shade at the Byzantine Empire which is a weird target, I'm not sure what ideological benefit he gets from that. If it is that incident it definitely did not go down the way he's describing it. As is always the case it was way more complicated.

I find myself recommending this a lot here, but it's because I think it's the best of the approachable Crusades histories, but if you want a good account of the history of the Crusades Thomas Asbridge's The Crusades is a great place to start. It's not perfect and he certainly has his biases but overall it's a great work and it covers pretty much all the medieval crusades in at least some detail.

If you want a shorter work more focused on just the big 3 Crusades Jonathan Riley-Smith's The Crusades A Short History is good for that.

The Muslims focused on Christians and Jews…forcing conversions, plundering and mortally wounding apostates.

This is horrifically wrong in a way I don't see addressed here yet, so an add-on for the existing answers:

There were large christian and jewish communities in the region under Islam. While it wasn't equality in the modern sense, it's certainly better than what the crusaders brought. The crusaders massacred large segments of the jewish population, both in the holy land and in Europe as they departed, and kidnapped many more. Using Muslim oppression of Jews as an argument for the rightness of the crusades is precisely the opposite of a correct understanding of the crusaders relationship with jewish communities. Some jewish communities even fought against crusaders on the side of their Muslim neighbors (in Acre), and certainly none actually supported the crusaders (which might be expected if the crusaders were actually better about treating jewish communities than Muslim rule was).

/u/Valkine's response is great, but I'd just add to like another point as to why that article is a bit strange. The author frequently references "the Crusades" in plural, meaning that he is talking about, well, the Crusades, as opposed to the First Crusade or the Second Crusade or any specific Crusade.

The problem is that "the Crusades" is a term used to describe a loose collection of wars that were fought at different times by different people with different goals.

For example, I'm having trouble thinking about how one can rationalize the Crusade called for by Pope Innocent III against the supposed "Cathar" heretics in Southern France - the Albigensian Crusade - as a defensive war against Muslims, given that the people the Crusaders were fighting in that Crusade were decidedly not Muslim. The same goes for the Baltic Crusades fought in Northern Europe - Prussian, Estonian, and Lithuanian pagans don't exactly fit into the category of Muslim, do they? And there's always the Fourth Crusade - which was, in fairness, launched to fight actual Muslims, but ended up sacking the Christian cities of Zara and Constantinople instead.

The Crusades were a response against Jihad, which is obligatory against non-Muslims entering “Muslim lands’”. (Muslim lands are any lands invaded and conquered by Islam.)

This certainly was not true, and Christians were considered "people of the book" in Islam and permitted access to pilgrims. That said, occasional extremists did push back against Christian visitors.

One of the justifications for the crusades that I haven't seen mentioned yet was the burning of the Church of the Holy Sepulchre, by Fatimid caliph Al-Hakim bi-Amr Allah in 1009. This led to a papal bull calling for Muslims to be driven from the Holy Land by Pope Sergius IV. Although the crusades were 100 years later it greatly angered Christians and would be used as justification for Christians to retake it in a sort of "armed pilgrimage" that the first crusade was.

hi! if you're looking for more information about the Crusades, there are some excellent posts in the FAQ

• Motivations for the Crusades

There are definitely some elements of truth in there, but I wouldn't characterize them overall that way.

The First Crusade was motivated partly by a call from the Byzantines for assistance, and partly because Christian pilgrims suffered some very atrocious attacks on the road to Jerusalem.

I don't think we can ever characterize any group as having "pure" motivations (is that your characterization or his?) but it is indeed certainly wrong to characterize the First Crusade as an example of pointless Western aggression as is so common on here. The West was indeed responding to valid reasons.