This is hilarious. So people are willing to spend hundreds to secure an oustide entry door, but still have regular old glass windows, or better still, live in a stick-built home, like most houses in this country. I can almost walk through an outside wall into a stick built home. Most stick built homes could have no windows or doors at all, and I could still get into them in less than a minute!
In some cases that might not be an exaggeration. Entire subdivisions in Florida have been built with Therm-ply, essentially heavy-duty cardboard sandwiched by aluminum foil, as the structural sheathing. This is covered in vinyl siding which has to be nailed into the framing as you can't nail to Thermo-ply. On the interior there is the cheapest 1/2" drywall available. In keeping with the overall outstanding quality the vinyl was poorly installed so that considerable amounts of rain ran inside the wall.
Good thing rain and moisture is never an issue in Florida. <dripping sarcasm>
After a couple of years the fiberglass insulation was soaked, the Thermo-ply had soaked up water and turned to wet cardboard with de-laminated aluminum foil, the vapor barrier had sagged and the drywall was soggy. In spots the framing had begun to rot and carpenter ants had moved in. I literally saw a carpenter shove his hand through an exterior wall. Hardest part was getting his hand through the siding. I suspect that in the worse spots you could jump through the wall as long as you were careful to avoid the framing and wiring.
On the other hand even a house sheathed with OSB would be pretty tough to get through without tools. Plywood harder still as it has more impact resistance. I have knocked holes in OSB I could put my hand through with a half-dozen swings of a hammer. With plywood I go for the saw.
If you use a chainsaw, preferably one with a carbide toothed chain like many fir departments use, you can cut a door pretty quick. Faster still if you avoid the framing. Backing a truck through a corner works also.
Funny thing is entries through the wall is possible but it remains exceptionally rare for burglars. Most go through a door or window. A lot simply walk in through an unlocked door. Even firemen tend to like doors more than windows. Walking in, and evacuation, is far easier through a door. Thieves usually realize that they are vulnerable while climbing in or out of a window. They also know that he sound of breaking glass is more likely to cause a bystander to investigate and/or call police than someone shouting 'fire'.
Also windows are a bit different than doors. On one side glass is always vulnerable. On the other windows are usually harder to physically get to, and because they aren't opened as often as doors they are in some ways easier to reinforce. High and narrow windows can be too much trouble to mess with. Bars on the outside and Plexiglas on the inside slow down even the firemen. The Plexiglas on the inside is an issue for burglars because you have to break the glass before you get to it. There are also high-tech films that make glass hard to get through.
The rough opening can be reinforced much the same way the door opening was with plywood surrounding and aluminum plates. Wind rated windows have much tougher than the typical frames. Screwed at frequent intervals with long screws through a metal plate and deep into the surrounding framing the window is resistant to being blown or bashed in.
The stops on windows can be replaced by aluminum extrusions that are screwed all the way into the rough framing.
Of course there are rules as to what and how you can do things. Most codes require that at least one window in each bedroom be large enough to allow a fireman to get through. Firemen need to get in and you need to be able to get out. The idea here is not to live in a bunker. Rather it is to harden those openings most likely to be attacked by burglars and to match the level of security to the risk. A back door or ground-level window that opens onto a blind ally, where any burglar has privacy and time to work on it, needs to be tougher than one that is immediately visible from a busy street.
The idea that a security system or gun is good protection overlook several things: Most response security systems are easy to trigger if nobody is home. It is not unheard of for burglars to trigger an alarm repeatedly so the address gets a reputation for false alarms. By the third or forth time people ignore the noise. Some organized burglars know the response times of the police and work fast to get in and out before police can arrive.
Even the 'armed response' security organizations are not what many think. Most of the armed responders make just a bit over minimum wage. No rational human being will rush to a potential shootout for short money. Better to delay and arrive after the bad guys are gone. Then it is just a matter of filling out paperwork. Getting a call is cause to have another cup of coffee.
Even if you have a gun the odds are you won't be home when they try to break in. Experienced burglars work hard to make sure nobody is home. Often waiting for people to leave. Once you're gone that gun you were using to protect your property is a prime target for the thief.
Of course one of the biggest ways to maintain security is to limit the motivation of any potential burglar. Most are willing to work much harder if they know there are rich pickings inside. Faced with a situation where they don't know, and the chance there is very little to gain by breaking in, their enthusiasm and work ethic tend to be rather weak.