Shortly after last November’s terror attack in Paris, our shul started to post a policeman outside the front entrance every Shabbat morning.   Some local synagogues have had security details for a while: policemen, or shul members with uniforms and bluetooth ear devices, some trained in krav maga. Now, many more Jewish institutions do.

Officer MacDougal is a pleasant man. He is short and a bit heavy-set. With his bright-yellow reflective vest, he looks like a crossing guard on break.

Does Officer MacDougal make us safer? Can he prevent a terrorist attack? I don’t know. Do you?

At first, I was troubled by the presence of a uniformed officer outside our door. True, many Jews all over the world cannot congregate without protection, to meet or to daven. In many countries, this has been the case for a long time. To enter shuls in Europe, you have to show a passport, answer questions, or register in advance with a communal office. Twenty years ago, my son and his friends, all Yeshiva University students with kippot and flowing tzitizit, were turned away from a Rome synagogue. Sorry, they were told, we don’t know you. Pray somewhere else.

So I know that security can be needed. I just didn’t think it was needed here.

Having prominent security outside a place of worship has both symbolism and substance. The problem is figuring out what the symbol means and what the substance is.

First the substance: does security work? Obviously, it sometimes can. But which times? What kind of security is real, not just a gesture? Security can make people feel safe. But are they safe?

When our shul put up a new building five years ago, a member who grew up in Lausanne, Switzerland offered to help with security design. He said that security was the only real Jewish activity in his small and shrinking home community. The Lausanne synagogue was built set far back from the street and surrounded by concrete bollards. These were to protect it from being rammed by an explosive-laden truck bomb. We lacked the land and the stomach to implement this, and politely declined. Perhaps we should reconsider. Or is Officer MacDougal good enough?

Being safe is one thing, feeling safe is another. Consider Israel. Now.

A man I know shops weekly in Mahane Yehuda in Jerusalem. During our last visit in October, when the stabbings had already begun, he continued to shop there armed with a sharp stick. The place was empty, he reported. Farmers had stopped sending produce, which would have rotted, unbought.

I spoke to him last week. “It’s back to normal,” he said. “Lots of people.”

Why is that, exactly? Is everything OK now? Judging by the daily news reports, it certainly doesn’t seem that way. Yet people are shopping again, so they must feel safe. Perhaps the routine of life reasserts itself. Accepting that the new normal means never again shopping in Mahane Yehuda may be too much to accept.

A friend’s son is spending a gap year at a yeshiva in the Old City. How is that going?

“At the beginning, they were in lockdown,” he said. “They weren’t allowed to leave the building.”

And now?

“Now they go everywhere,” he said.

Does that make any objective sense? If it does, the sense escapes me, other than to confirm that safety is at least in part a feeling, and feelings depend on more than facts.

What about the symbolism of security? As a tourist in Europe, I saw all that obtrusive synagogue security as a statement, one that said, “Other people can congregate and shop and pray, but not Jews. We live here, but we do not belong here.”

I was an outsider, though. It’s possible that locals didn’t look at it that way at all. I didn’t ask them. I didn’t know them to ask.

That is why the sight of Officer MacDougal bothered me. I saw his presence as sending a message I didn’t want to send. As an American, I think I do belong here.

If you wish, you can roll your eyes at my naivete. You may have your opinion about my long-term prospects here as a Jew, but I have mine. This is where I live, and that is how I feel.

Perhaps I am overthinking Officer MacDougal. Maybe he is just part of the new normal for everyone. After all, more security is everywhere. There have been bloody attacks all over the US, many seemingly random: in schools, movie theaters, shopping malls. Time was when you could just stroll into a public building or walk right up to an airport gate and onto the plane. Who remembers that? In a couple of years, who will remember when you could just walk into shul without nodding good morning to a cop?

Last Shabbat I was visiting in the next town. I chatted with a friend doing shemira outside his shul. His group has had patrols for a while. He wears a dark uniform labeled ”Security” and carries a concealed walkie-talkie.

“Did you and the others who do this ever stop anyone suspicious?’ I asked.

Not that he could recall.