The phrase "combat boot" has more than one meaning, and several different boots can serve in this capacity, depending on the need of the wearer.
First and foremost, though, the boot has to fit.
In the late 1930's, as the US military saw WWII approaching, they realized they would need to put boots on millions of men.
The US Military's researchers devoted six months to the study of the human foot amongst the widely varied American population.
From this study they came up with the "Munson Last," a master foot shape that would fit the largest numbers of people, comfortably.
Further, the military provided a broad range of sizes and widths within the guidelines of the Munson Last.
Google
Munson last combat boot and mostly Cove and HH boots will surface.
I think HH exists as a subsidiary of Cove, or the other way around.
In any event, Cove makes a faithfully accurate modern version of the Corcoran Jump Boot.
HH sells what seems the same boot without calling it a Corcoran, for less than Cove sells the Corcoran.
http://www.anchortex.com/cgi-bin/shopper.cgi?preadd=action&key=C200348
Same boot called a Corcoran and made by Cove:
http://www.anchortex.com/cgi-bin/shopper.cgi?preadd=action&key=C200141
I'd go with the real thing, just in case HH has cut corners.
Cove/HH also makes a Tanker's boot, based on the Munson Last, but having leather straps and buckles instead of laces, and no toe cap.
It has merit.
http://www.shoeshackonline.com/site/623303/product/5407
The Corcoran boot has remarkably flexible and light leather (glove leather) on the instep, sealed full-tongue (I can't remember the correct term for this type of tongue, but it means waterproof), and ankle/shin shaft.
The toe and the heel have double layers of very tough, molded leather.
The molded toe provides a large (wiggle your toes) comfortable and cool toe box (cool in summer and warm in winter) that doesn't crush, and pops back if it does.
The molded heel, with the help of the full lacing and soft leather of the instep and ankle/shin shaft, completely controls the foot without creating a feeling of claustrophobia or tightness.
The Munson Last, soft/supple leather, plus the big molded toe box and molded heel makes the most comfortable fitting boot most people have ever experienced.
They have put this boot on top of a modern Vibram sole made exclusively for Cove.
This sole resists oil (more important than most people realize), does not mark floors, wears well and yet positively grips a wide variety of natural and man-made surfaces.
I consider this specific sole the best all-around sole I have experienced.
Designed originally as a paratrooper's boot, this boot supports a high level of athleticism, walking and running.
It weighs less than any other boot of this type I have worn, by a wide margin.
This boot has a perfect balance of lightness, flexibility and support.
Because of its lightness, it will not hold up to years of hard field use, but it will take severe short term abuse and will also serve decades as a uniform boot.
Because my company pays for my boots, I buy a new pair of Corcorans every year.
They take one day to become glove comfortable, and more comfortable than any boot of my experience.
In contrast, the Marine Corps of the 1960's issued a much heavier boot, with a non-lugged Vibram sole.
The Marine Corps intended these boots for extended, heavy field use, with minimal service and repair.
They worked great, but weighed considerably more than Corcorans.
A three-mile run in Corcorans felt like a stroll in the park compared to the same three-mile run in the much heavier Marine Corps field combat boot.
For total indestructibility, fit and quality, no boot on earth compares to White's Smoke Jumper.
http://www.whitesoutdoor.com/store/product.php?category=Boots&id=701
These boots fit exquisitely, weigh too much, and cost more than anyone should ever pay for a boot.
Please note that the White's site lists the 10" Smokejumper for $405.
I have owned a pair of Whites, and can confirm their value.
They weigh three times as much as Corcorans, but don't feel like it on the foot because of their design and fit.
This boot will see its wearer through anything, anywhere, anytime.
Still, I find Corcorans much more practical, more cost-effective, and more comfortable for non-combat wear around the office.
In an emergency they'll get you there and back, comfortably and athletically.
The folks who designed the Corcoran really, really, really thought it out, and it stands as one of those unique human artifacts that has attained perfection for its intended purpose (jumping into the unknown and moving fast once on the ground).
And Cove has remained totally faithful to the design, except for the improved sole.
Munson Last.
Wear Corcorans once and you'll wear them forever.
Oh, and with a little polish and brushing they look sharp!