The ship — festooned in banners reading “Defend Europe” and “No Way — You Will Not Make Europe Home” — missed its planned media launch when the Egyptian authorities held it up in the Suez Canal. Then the group’s Italian leader missed his plane to Sicily, where the group planned to depart. And some of the crew members of the ship chartered to stop asylum seekers themselves sought asylum in Cyprus.

The greatest indignity came Friday when at 9 a.m., European naval aircraft noticed the ship, the C-Star, in apparent trouble with its engine turned off outside of Libyan waters in the Mediterranean Sea. The authorities searched for the closest vessel to come to its aid and found, only a few nautical miles away, one of the very ships the young hard-right activists had hoped to stop.

“They refused our help,” said Michael Buschheuer, a spokesman for the Sea Eye, a ship chartered by German humanitarians to rescue migrants. “So we just passed them and went on to our normal working day, which means keeping an eye on people who are really in distress.”