DUBLIN, Ireland - Sometimes words aren't necessary. That was the case Tuesday when Queen Elizabeth II placed a wreath in Dublin's Garden of Remembrance to honor the Irish rebels who lost their lives fighting for freedom from Britain.

The queen became the first British monarch to set foot in Dublin for a century. Her four-day visit is designed to show that the bitter enmity of Ireland's war of independence 90 years ago has been replaced by Anglo-Irish friendship and that peace has become irreversible in the neighboring British territory of Northern Ireland.

The ceremony under steel-gray skies was simple and direct, its meaning clear.

There were no apologies, no acknowledgment of misdeeds, but the presence of the British monarch on ground that is sacred to many Irish was a powerful statement of a desire to start anew.

Helicopters and fixed-wing aircraft patrolled the skies and sharpshooters kept watch on rooftops during the ceremony for any attempt by Ireland's most extreme nationalists to disrupt the event.

A few hundred supporters of Irish Republican Army dissident groups did clash with police on the security perimeter a half-mile away, but the trouble did not interrupt the queen's procession through Dublin.

Nor did the dissidents' efforts overnight to draw attention by planting a pipe bomb in a bus 15 miles from Dublin and three hoax devices in the city itself. Later, the dissident IRA protest degenerated into hooliganism along a working-class street where antipolice sentiment runs high.

By nightfall, at least 21 were in custody.

Earlier, as the queen stood in silence alongside Irish President Mary McAleese, a flock of black balloons floated above, a silent protest by the nationalist Sinn Fein party. But the event marked a successful first day of the queen's groundbreaking visit, a trip aimed at demonstrating the former foes had reconciled their differences.

"It's not uncommon for a head of state to lay a wreath at a site of mourning," said historian Mary Daly, "but in this case, you get the British monarch laying a wreath at a memorial garden that remembers many people who took up arms against her ancestors.

"What it reflects is sympathy, recognition of this independent Irish nation."