If countries were like high school, Canada would be one of the most popular kids in the class. More than 250,000 immigrants and refugees chose to begin new lives here last year. And scores more are waiting in line for a chance to start over in a country known around the world for its diversity, tolerance and prosperity.

Canada’s reputation is well deserved. We enjoy one of the highest standards of living in the world. Our Charter of Rights and Freedoms guarantees basic democratic rights that citizens of many countries can only dream of. Our publicly funded health system provides care to all who need it, regardless of income or social status. High-quality education, too, is widely accessible across the country.

But what appeals most to many newcomers is that being Canadian does not mean having to fit into a single mould. Muslim women who wear headscarves, orthodox Jews and recent immigrants from China and India are just as Canadian as those who claim Loyalist roots.

That’s a good thing. Our diversity, our willingness to remake ourselves and our ability to embrace political, cultural and religious differences, for the most part without conflict, are a source of strength of which Canadians can be rightly proud.

Yet for all that, we cannot afford to be complacent. Our social fabric is being stretched by forces that threaten to erode the harmony and prosperity we have so carefully built. In the face of these threats, we should all pledge to do better, and demand our leaders do the same.

Poverty is leaving too many Canadians behind. Nearly two decades after Parliament unanimously pledged to eradicate child poverty by 2000, many young people are still going to school on empty stomachs. Their parents may be working low-wage jobs, unable to piece together enough hours of work or subsisting on welfare.

Despite promising signs, particularly in Ontario where the government of Premier Dalton McGuinty has recently created a new child benefit for low-income residents and committed to raise the minimum wage to $10.25 an hour by 2010, too many families are still not sharing in the wealth that surrounds them.

Is that really the kind of Canada we want to live in ?

On the environment and global warming, too, Canada is following rather than leading. Prime Minister Stephen Harper has set out an unambitious plan to take Canada only 70 per cent of the way to meeting its 2012 target under the Kyoto Protocol by 2020.

Better late than never, some might say. But given the potentially disastrous effects of global warming, Canadians should insist their leaders take aggressive action. And we should all be ready to do our part.

Cracks also are showing in our multicultural mosaic. Terrorism and security concerns have prompted some to question our liberal immigration policies. And debate is simmering, particularly in Quebec, over just how far Canada should go to accommodate minorities.

Often lost in these short-sighted discussions is that it is exactly our differences that have made this country strong. We are a model of diversity and openness in a world that has become dangerously fixated on what separates people, rather than what brings them together.

If the challenges Canada faces are daunting, they are not impossibly so. That’s why we should rejoice in our great achievements. However, we also should think about how we can make "our home and native land" a better place for all who live within our borders.

After all, equality, open-mindedness and concern for others are just as Canadian as hockey, beer and doughnuts.

On this Canada Day, our 140th birthday, all of our Canadian values are surely worth celebrating.