Editor’s Note: Lt. Gen. P. K. “Ken” Keen is a retired Army officer who previously served as military deputy commander of United States Southern Command. He is the associate dean of leadership development at Emory University’s Goizueta Business School. The views expressed in this commentary are his own. View more opinion at CNN.

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When I retired from the Army in 2013 as a three-star general, I thought that retired military officers should not make public political statements. We take an oath to uphold the Constitution of the United States, not to pledge alliance to certain political leaders. But the events of the last week have led me to reflect more deeply about what service to our country means. I can no longer remain silent because more than anything, it is a time for all citizens and leaders to stand up for our democracy. We must find ways to heal a very divided nation.

Ken Keen

After serving in countries where democracy and the rule of law were goals the people there could only aspire to achieve, it has been more than heartbreaking to see what I could never imagine happening in our own country. President Donald Trump must be removed from office as soon as the law allows, either by impeachment, the 25th Amendment, or best yet a voluntary resignation (as unlikely as that is).

Like most Americans, over the last week I was horrified by the scene that unfolded in our nation’s Capitol. The United States of America has been a shining light for the rest of the world when it comes to peaceful transitions of power. We are a country that, since the Civil War, even under the most challenging of times, passed power from one elected president to another in accordance with its historic Constitution. Even the losers of the closest of elections passed power with dignity and respect. That light has been dimmed during this historic crisis.

Our leaders on both sides of the aisle should take action to hold everyone involved in the attack on our Capitol accountable. This includes not just those in the mob that killed a Capitol Police officer and vandalized the Capitol, but also those who incited the violence, including Trump.

I have mixed feelings on which action is most appropriate. I do believe, Trump needs to step down now or Vice President Mike Pence needs to lead the effort to invoke the 25th Amendment, which would remove Trump from office.

If the Vice President does not have the courage and leadership to take this action, then Congress should take matters into its hands. The House, which will vote on impeaching the President on Wednesday, should send its article of impeachment, assuming it passes in the House, to the Senate after President Biden’s inauguration. Leaders must lead, or they should step aside and resign if they are fearful for their personal safety or future of their political career.

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We ask our military and our young men and women in uniform to put their lives on the line every day in defense of our country. Right now, many of them are on the front line in Afghanistan and other places around the world. If political leaders are not ready to do the same and put their careers at risk by taking a stand against those whose actions may have provoked or encouraged the attack on our Capitol, resulting in the death of five Americans, they should resign. They are in the wrong role and do not deserve the honor and privilege to be our leaders. They should be held accountable and voted out of office.

I realize many friends, some family, and others disagree with this view. I do not take it lightly. I also believe our country and institutions will endure this crisis. But now is the time for decisive action. My hope and aspirations for my children and grandchildren is that today’s leaders can navigate this crisis to bring our nation together and ensure the light of democracy shines even brighter for future generations.