This Fourth of July, America begins a year of celebration and reflection as we prepare for next year’s semiquincentennial — 250 years since our Founding Fathers courageously declared independence from Britain.

Milestones provide an opportunity to reflect on the significance of a moment within a longer storyline. Yet, for most Americans, July 4th is rarely a milestone. More often, it is a brief acknowledgement and — truthfully, for most — a day off to grill and watch fireworks.

But on this Fourth of July, how should we think about this milestone, the last 249 years, and the 250 to come?

We should think about our democracy with great hope and determination. At the same time, we should recognize that our democracy is facing significant challenges  — protests, political violence, external threats and heightened polarization.

American democracy is exceptional, fragile and resilient — factors that compel every American to recommit to strengthening it. Our Founders cast a vision for a nation, driven by democratic principles, not monarchy. A nation in which the power was in the hands of the people, not an unaccountable tyrant. A nation in which rights were to be protected, not subject to the whim of an unelected leader. Our founding defied all understanding of government.

And — in the glorious paradox that is the United States — the very visionaries who formed our democratic nation violated them in the most profound ways through slavery and disenfranchisement.

The exceptionalism of our nation lies in the lofty vision of our Constitution and the Bill of Rights, as well as the long struggle to ensure that all Americans could fulfill the promise of these founding documents. The moral principles and self-correcting mechanisms of our democracy have become the beacon and timeless tools of struggle for all Americans and an inspiration for the world.

What is exceptional is our journey, grounded in democratic principles and the never-ending struggle to live up to those principles.

As we see from countries worldwide, democracy and freedom can be taken from their people by those, elected or unelected, who choose to violate democratic principles and consolidate power for personal gain. Today, American democracy faces threats, foreign and domestic, that seek to weaken our nation.

As President Ronald Reagan famously said, “Freedom is a fragile thing, and it’s never more than one generation away from extinction. It is not ours by way of inheritance; it must be fought for and defended constantly by each generation, for it comes only once to a people. And those in world history who have known freedom and then lost it have never known it again.”

Our democracy is resilient. Democracy requires the persistent, principled vigilance of courageous patriots. Our Founding Fathers threw off the yoke of colonial rule and forged a new democratic nation, a shining city on the hill. The principles of our nation and the courage of our patriots have enabled our country to flourish.

Let us make this July 4th a milestone in recommitting to strengthening American democracy.

Nicole Bibbins Sedaca is the Kelly and David Pfeil Fellow at the George W. Bush Institute.