This week I was saddened to learn that conservative stronghold Robert Novak was lost to his long battle with brain cancer. While his life was long and full, his loss will be keenly felt.

Bob was one of the old guard who defied easy description and refused to let anyone, Republican or Democrat, settle too quickly. Bob never let political leaders get away with the easy route, even when he was their ideological match. He admired toughness and strength, because that was what he himself exhibited.

Bob was born in Illinois and began his journalistic career early, before even graduating high school. Then, still a young man, he served his country as a lieutenant in the Army during the Korean War. He found his calling, though, in serving the country through his writing, and over the past several decades became a versatile commentator and the writer of the longest-running syndicated column.

During my father’s era, his column, co-written with Rowland Evans, was known as the “bulletin board of the Reagan administration,” not because he was a Reagan apologist, but because he had the connections and the determination to keep the stories coming. Love him or hate him (and there were plenty of people on both sides), you can be sure that no one could avoid him.

And he did more than just report. Before and through my father’s run for the presidency, Novak spearheaded a major push for fundamental tax reform, one which grew into a legacy. In the time of the highest taxes this country has seen, he fought for ideas and solutions, not just the status quo.

Bob was a mentor in his field and an inspiration beyond. His column not only served to provide honest, provocative commentary from a conservative perspective, but in it he also demonstrated his formidable investigative skills. Novak conducted his investigations with diligence and care, working to avoid the increasing pressure for speed over accuracy, one aspect of his integrity which will be missed by this entire community.

CNN put him on the air in its first week, and for years he co-hosted “Crossfire,” sparring with all his considerable insight and determination. His deep understanding of all things “Washington” allowed him to shine a light on these workings and put them on display before the American people with his unique skill.

Through Bob Novak’s eyes, we were able to see the grit and glamour of the political system, to call it to account, and to press for answers and accountability. In a liberalizing system, he courageously wrestled against the tide, moving in the opposite direction, fighting for small government, lower taxes, and limited powers. He has left a great void.

Bob Novak was a force to be reckoned with after five years reporting in Washington. After 50 years, he has become a legend. Republicans and Democrats can both agree on one thing — Bob Novak was a man of principle and gritty determination. American politics will not be the same without him.

Mike Reagan, the elder son of the late President Ronald Reagan, is chairman and president of The Reagan Legacy Foundation.