These notions were deeply personal to the Second World War veterans who listened on the neatly mowed grounds of one of Canada's more heartbreaking military cemeteries.
The graveyard holds the remains of 1,350 Canadian soldiers, killed in the waning days and weeks of the war as the Nazi Germany went through its final, convulsive death throes. They are among the more than 7,600 Canadians who died to free Holland.
Harper remembered them as heroes.
"The heroes who liberated the Netherlands, like the men and women who serve our country today, understood that when there arises a great evil, a threat to all the things that define our existence as a free and just people, such enemies must be confronted," he said, at the first of two commemoration he'll attend while in the Netherlands.
"But only the veterans with us today can really know the fear and desperation they must have sometimes felt or the courage and resolve it took to press forward ... And why? Because they knew, they understood deeply, that there are some things on earth worth fighting for, worth dying for. It was true then; it remains true today."
Linking the horrors of the past with brutal reality of today was persistent theme, not only for the prime minister, but for his Dutch hosts too, at the trilingual service just outside this sleepy village, 59 kilometres northeast of Arnhem.
When Harper met Dutch Prime Minister Mark Rutte they talked about fighting the Islamic State and maintaining a firm position on Russia.
But for Don Somerville, 92, a former sapper who served as a combat engineer, the world today is troubling.
"I wish we'd learn a lesson to start with and not have all this war and stuff," said Somerville, who lives in Mississauga, Ont. "There's no winners in a war, you know."
The prime minister said each headstone is a stark reminder that doing the right thing often comes at a great cost — but the cost must be paid.
"When tyranny threatens the free, when cruelty torments the innocent, when desperation overwhelms the human spirit, we choose to respond, we choose the high road forward, not the easy way out."
The hollow sense of loss that accompanies war hardened Somerville's features as he stared at the names on tombstones, which raised long-absent faces from the deep recesses of memory.
"A lot of thoughts go through your mind when you look down there," he said, after a lingering look at one marker. "You see the ages and you think how lucky you are to be here today."
Frank Graham had a long war as an artillery private with the 1st Canadian Division, landing in Sicily in August 1943 and fighting his way through Italy and northwest Europe before being wounded just before the end.
"Well, I tell ya, it got so after a while I didn't give a damn anyway," he said. "You take it that way and it don't bother you too much. But if you start worrying, you're gonna be in trouble."
The Dutch, renowned for their appreciation of their Canadian liberators turned out by hundreds at the cemetery, young and old in a display that never fails to move Graham.
"I can't explain it. My heart isn't big enough," he said. "It is such a different feeling when I get in here. I feel like, not at home, but I feel relaxed. I feel myself, mostly. Because that's the way they are."
A helicopter swooped low over the cemetery at the conclusion of the emotional service and showered poppies over the crowd, which included Dutch royalty.
Jim Summersides, a former private who served with both the Devil's Brigade commando unit and the 48th Highlanders, said he feels a personal debt to each of the fallen.
Asked why he keeps coming, he answered: "Memories."
"You get a flush of remembrance," said Summersides, 90, of Welland, Ont., "The best men we left here, I believe in places like Holton."
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