That's the series title of four articles you'll find at the Conservative Treehouse. They're very long and detailed, so much so that I won't even try to excerpt them here. The four are:
Sundance offers these considerations (in the fourth article) about why the raid was mounted.
In short, President Trump declassified documents that show how the institutions within the U.S. government targeted him. However, the institutions that illegally targeted President Trump are the same institutions who control the specific evidence of their unlawful targeting.
These examples of evidence held by President Donald Trump reveals the background of how the DC surveillance state exists. THAT was/is the national security threat behind the DOJ-NSD search warrant and affidavit.
The risk to the fabric of the U.S. government is why we see lawyers and pundits so confused as they try to figure out the disproportionate response from the DOJ and FBI, toward “simple records”, held by President Trump in Mar-a-Lago. Very few people can comprehend what has been done since January 2009, and the current state of corruption as it now exists amid all of the agencies and institutions of government.
. . .
Given the nature of their opposition, and the underlying motives for their conduct, there is almost nothing they will not do to protect themselves. However, if you peel away all the layers of lies, manipulations and corruption, what you find at the heart of their conduct is fear.
. . .
The existence of Trump is a threat, but the existence of a Trump that could expose their corruption…. well, that makes him a level of threat that leads to a raid on his home in Mar-a-Lago.
Makes sense to me.
If you aren't interested in the "meat on the bones" of why all this happened, you don't need to read any further. If you are interested, I think Sundance provides all the background you need to understand what happened, and why. I highly recommend reading all four articles, and keeping copies for future reference.
As you read them, consider also the points I advanced yesterday. They dovetail nicely.