Um... Matt. Your choice of article fails to cite any reference material or original research. The only mention of tangible data is from a strawman opinion poll whose existence we have only the author's word for. The article opens with a false analogy, which quickly turns into a false dichotomy:
guns -> gun violence , no guns -> knife violence | gun violence = knife violence
Probably in an effort to win over the centre-left, it is then escalated into anti-red propaganda:
government of China = communist = corrupt, evil, and/or tyrannical | any law enforced by same = inept, self-serving, and/or tyrannical
From here on, the author simply rants foolishly about what he assumes (or would like his readers to assume) is going on in the liberal camp.
It's a shame research results like this [the strawman opinion poll] won't make a difference, because liberal gun control efforts aren't based on science [which fails to make an appearance anywhere in this article], instead they are "faith-based," worshiping at the altar of big government and liberal policy.
The list that you quote from this article is as baseless as it is vague. At no point does he mention that all or any of these features even have been used to define the term, let alone who is using them.
Here are the deadly features liberals can use to define an "assault knife:"
To "assault" is simply to attack or threaten to attack, which would mean all weapons are assault weapons. The term appears to be a misnomer for "combat knife", which is a class of knife originally intended for use in a military combat scenario. The misnomer is not a liberal construct, nor in any way specific to liberals.
Blade has a depression running parallel to the edge, often called a "blood groove.
This is not a feature of any kitchen or utility knife I have ever seen. They do appear on combat knives, "survival knives", some bayonets, and some hunting knives.
Knife has the ability to fold like a folding stock
This is just used by lawmakers to describe switchblades. It has no direct relation to knives designed for killing people, so it shouldn't even be here.
Knife may be attached to a rifle like a bayonet
That would be a bayonet, which is only useful in warfare (and possibly for hunting tigers, but that isn't exactly a common occurence in the U.S.).
Knife handle has indentations for fingers like a pistol grip
Many knives at least have something sort of like this, but the description is simply too vague to be certain of what the author means.
Knife has a guard to protect the hand
This would relate to combat knives and swords, which are used primarily for the same purpose.
Knife may be used in conjunction with a shield
Swords again, but the correlation is tentative at best. No law pertaining specifically to one thing should specify it as possibly being used in conjunction with some unrelated thing.
Knife has a scabbard that may be attached to a belt
A common feature among swords, combat knives, and survival knives.
As you can see, most of the features he lists are related to combat knives, swords, and survival knives which are virtually the same as combat knives.
The writer was stapling a bunch of potential qualifications to the knife to show how ridiculous said qualifications would be, and they don't all apply to one knife.
And if one were to pass a law specific to Cadillacs, you would see a similar list of potential qualifications. Not every Cadillac has fins, a hardtop, gull wing bumpers, bullet-shaped bumper guards and tail lights, and an external rear-view mirror. Should we conclude that the Cadillac, in fact, does not exist?