On June 29, 2004, at 12.28pm, I flew on Northwest Airlines flight 327 from Detroit to Los Angeles with my husband and our young son. Also on our plane were 14 Middle Eastern men between the ages of approximately 20 and 50 years old. What I experienced during that flight has caused me to question whether the United States of America can realistically uphold the civil liberties of every individual, even non-citizens, and protect its citizens from terrorist threats.

On that Tuesday, our journey began uneventfully. Starting out that morning in Providence, Rhode Island, we went through security screening, flew to Detroit, and passed the time waiting for our connecting flight to Los Angeles by shopping at the airport stores and eating lunch at an airport diner. With no second security check required in Detroit we headed to our gate and waited for the pre-boarding announcement.

Standing near us, also waiting to pre-board, was a group of six Middle Eastern men. They were carrying blue passports with Arabic writing. Two men wore tracksuits with Arabic writing across the back. Two carried musical instrument cases — thin, flat, 18in long. One wore a yellow T-shirt and held a McDonald’s bag. And the sixth man had a bad leg — he wore an orthopaedic shoe and limped.

When the pre-boarding announcement was made, we handed our tickets to the Northwest Airlines agent and walked down the jetway with the group of men directly behind us. My four-year-old son was determined to wheel his carry-on bag himself, so I turned to the men behind me and said, “You go ahead, this could be a while.”

“No, you go ahead,” one of the men replied.

He smiled pleasantly and extended his arm for me to pass. He was young, maybe late twenties and had a goatee. I thanked him and we boarded the plane.

We took our seats in economy (seats 17A, 17B and 17C). The man with the yellow shirt and the McDonald’s bag sat across the aisle from us (in seat 17E). The pleasant man with the goatee sat a few rows back and across the aisle from us (in seat 21E). The rest of the men were seated throughout the plane, and several made their way to the back.

As we sat waiting for the plane to finish boarding, we noticed another large group of Middle Eastern men boarding. The first man wore a dark suit and sunglasses. He sat in first class in seat 1A, the seat second-closest to the cockpit door. The other seven men walked into the economy cabin.

As “aware” Americans, my husband and I exchanged glances, and then continued to get comfortable. I noticed some of the other passengers paying attention to the situation as well. As boarding continued we watched as, one by one, most of the Middle Eastern men made eye contact with each other. They continued to look at each other and nod, as if they were all in agreement about something. I could tell that my husband was beginning to feel anxious.

The take-off was uneventful. But once we were in the air and the seatbelt sign was turned off, the unusual activity began.

The man in the yellow T-shirt got out of his seat and went to the lavatory at the front of the economy cabin — taking his full McDonald’s bag with him. When he came out of the lavatory he still had the McDonald’s bag, but it was now almost empty.

He walked down the aisle to the back of the plane, still holding the bag. When he passed two of the men sitting mid-cabin, he gave a thumbs-up sign. When he returned to his seat he no longer had the McDonald’s bag.

Then another man from the group stood up and took something from his carry-on in the overhead bin. It was about a foot long and was rolled in cloth. He headed toward the back of the cabin with the object. Five minutes later several more of the Middle Eastern men began using the forward lavatory consecutively. In the back, several of the men stood up and used the back lavatory consecutively as well.