They won't use utensils that have touched meat _since last being washed_. For kosher, you have to have permanent segregation of utensils etc.

This is fascinating. I have a hard time wrapping my head around how this is supposed to work though. Does this assumption never break down at any point? From the moment the iron is extracted and melted to the moment the knife comes into your hand... is there some kind of chain of custody certificate that says it's never touched anything impermissible? Are there entire kosher industries and factories I'm not aware of for making utensils and such?

The point is being simplified. Simply washing a knife will not make it suitable for preparation of kosher food; but there are methods that will.

Searching for "libun gamur" and "hagalah" will provide a starting point for the genuinely interested.

Oh wow I see, thanks, just Googled. For anyone else wondering, it depends, but you need to e.g. heat the utensil to get it red hot!

A brand new utensil is assumed to be kosher, since it's unlikely a factory is going to have food in it that would contact the utensils.

Also, a utensil is koshered by the same heat-level that made it non-kosher. So if used on a fire, it's koshered on a fire. If used only in hot water, then it's koshered in hot water.

It can get more complicated: Some things (like plastic, or wood) can never be koshered (except by removing a layer from the surface, for example by sanding) because they absorb too easily.

Red hot heat can kosher anything, but those substances can not withstand the necessary temperature.

Glass is interesting as it's considered impervious, and some hold that simply washing it is enough because nothing absorbs into glass.

Are the pots and pans used for dairy, meat and vegetarian foods ever washed in the same commercial dishwasher? This is impermissible in many kosher traditions.

I invite anyone who thinks keeping a kosher kitchen is straightforward to do some quick web searches on the topic.

It can be straightforward if you maintain two entirely separate kitchens forever :D It seems like the complexity comes in trying to chart a path through the grey area between 100% separate and 100% integrated.

And by Jewish halacha (law) you also need a watchman in the kitchen (mashgiach) making sure the rules are followed.

There is no realistic way NY can do this, and Jews are not expecting it. But there are Jewish organizations who are helping those who need it.

I recently learned that insects are not kosher, so some Jews don't consider figs to be kosher because of the fig wasps. There are probably more examples.

I wonder about honey then? Its the product of non-Kosher insects

It is specifically mentioned as permitted because it is not made by the bees, but is rather collected by them (from flowers).

This is in contrast to Royal Jelly which is not kosher.