After watching the video of the police tasering Muhaydin Mire, 29, now accused of the attempted murder of a 56-year-old man he attacked and seriously wounded at Leytonstone Station after shouting "this is for Syria", I suddenly realized something.
After living in London for almost 30 years - a citizen for over 20 of those - I realized something fundamental about my adopted country.
News of what happened at Leytonstone, of course, spread all over the world, so relatives and friends from the States got in touch.
After I assured them that I was okay, they then went on to ask why and how the Met dealt with a potential terror situation - without guns. It was so strange, so incomprehensible, something they could not imagine.
That's because the USA is an armed society. Arms are the equalizer; the avenger; the explainer; the revenge; and your best friend.
America has as many guns as it has people. So we're talking over 300million and counting.
There were over 300 mass shootings this year - and the year isn't even over yet. Each state regulates gun ownership etc. Since the United States is a federal structure, each state is a kind of mini-republic.
They pretty much do what they want. Which is great for many because there are Americans who heartily believe the federal government, Washington, to be a tyranny, even a foreign entity hell-bent on destroying individual liberty.
For Second Amendment zealots the right to bear arms, to own a gun, is an inherent right. And only God can take your gun away.
I asked friends and relatives in Chicago and LA how police forces in their cities would have dealt with Leytonstone. From my hometown, Chicago's south side:
"Ok. If someone shouted 'Syria' and then proceeded violently the CPD (Chicago Police Department) would just shoot. The SWAT team would of taken care of that London dude. No taser. And if you're a passerby whatever, hey, RIP, 'sorry for your loss' and so forth and so on. But boom! Everybody knows that. In your head you're always hitting the deck, getting on that floor as fast as you can. You're rehearsing. You make sure you have a gun so you don't get gunned."
Los Angeles:
"I think the police are afraid to admit they've hired military veterans. Most young veteran men and women under 35 have fought in either Desert Storm, Iraq or Afghanistan. You can't take a kid outta high school anymore and send him to cadet school. Ex-military is ready, willing and able, plus they need jobs. Here in LA, these ex-military have identified blacks and Hispanics as unpatriotic - just short of committing treason. You can't get combat out of an ex-soldier's head. So it's ugly here."
The New York Daily News' daily headlines rebuking pro-gun people - this one for those offering their prayers to the victims of San Bernadino is bravely leading, along with others, an attempt to rein in the National Rifle Association.
These anti -"Gun USA" people are labelling the NRA "terrorists" and as waging a "NRA jihad" against the American people. The Daily News is calling every mass shooter who played a part this year in the American Gun Nightmare a "terrorist". That's whether the outrages were done in the name of Islam, White Power, Black Power, against abortion or 'For No Specific Reason I Just Felt Like It'.
Of course I know that there are guns in the UK and that there are individuals and communities who live under the threat of them every day. But what I'm arguing against is the routine arming of the police - and of ourselves. Because if you own a gun you're more likely to use a gun. If you produce a gun you get answered with one. If everybody is armed, you'll get armed, too. And then the world becomes a battle between you and What's Out There, Who's Out There.
Just ask the family of the British man who knocked on a door in Texas in the early hours of the morning because his car had broken down and he needed help. He was greeted with a barrage of gunfire before he could even open his mouth. The householder was not charged. It was ruled self-defence.
And even if you're an American expat, with family and friends back in the USA, gun violence will eventually touch you, too. Some of my family lost friends at San Bernadino. They were just ordinary people at a Christmas party, a Christmas party in an armed society where you can buy an automatic weapon faster than you can buy a dart for your dartboard. Where you can strap your Uzi on your shoulder while you stand in the queue for your Big Mac with extra fries. Because owning a gun is more American than a Big Mac, more American than apple pie. A lot of people don't eat apple pies or Big Macs. But you better believe that they probably have a gun or know someone who has.
Yes, I want the UK to be safe. I want the police to have whatever they need to combat the maniacs out there who've hijacked a religion as a flag of convenience for their malignant psychodrama.
Train us to be more alert, too, to be more vigilant, more aware. But don't routinely arm our police. Don't routinely arm us. I really hope that never happens. Not ever.