Under fire for accepting gifts from supporters and in danger of being dropped from the Republican ticket in 1952, Richard Nixon went on national television to defend himself. It was true, he said: He'd been given a dog, a cute little cocker spaniel named Checkers. Well, his children loved that dog, and he'd be damned if he'd give it up. The public response was immediate and overwhelming. Nixon stayed on the ticket.

Mr. Martin, for his part, is under fire over his plans to assume the office of Prime Minister while remaining principal owner of CSL Group, a multinational shipping and real estate conglomerate worth nearly half a billion dollars. In a lengthy front-page interview with the National Post, Mr. Martin struck a similarly defiant note. Yes, he did own a shipping company. But, well, he really, really loved ships, and he'd be damned if he'd give it up.

"I just love ships," he told our Susan Delacourt. "I love harbours. I love ports." This wasn't about money. It was about a dream. "I've had this love affair with ships since I was five years old. I don't want to sell this company because I had this dream to build a multinational and I did it." And it wasn't just about him. It was about the country -- the national dream, if you like. If he were forced to sell CSL, it might wind up in foreign hands. "I just couldn't live with myself if this dream was turned over to another country."

So now we know. Paul Martin loves ships. And he loves Canada. Force him to divest CSL, and it would be some foreigner whose ships were registered offshore to avoid Canadian taxes. How much better if it were a Canadian -- and not just any Canadian, but the Prime Minister of Canada.

So far, Mr. Martin's emotional appeal seems to be working. Editorial commentary has been generally sympathetic, largely on personal grounds: It would be too harsh, many agree, to force Mr. Martin to sell the family firm, a business he had built -- well, bought from his employer, Power Corp. -- from a mere $189-million grubstake.

But no one's forcing him to do anything. All anyone has said he should do is to choose: between being Prime Minister and being in business. Given how much he loves ships, the choice should be obvious.

Would this prevent other businessmen from going into politics? Nonsense. It's perfectly possible to have a career in business and a career in politics. You can run a business, then become Prime Minister. Or you can be Prime Minister, then run a business. You just can't do both at the same time. It is hard to believe this even needs discussing.

Suppose Mr. Martin didn't own CSL. And suppose he became Prime Minister. And suppose he then proposed to purchase CSL, a large and diverse operation whose interests are affected by a vast array of federal regulations and policies. Would anyone say this was all right?

Or suppose he were not yet in politics, but was still just the humble CEO of a major international shipping company. Suppose he then proposed to run for Prime Minister -- while maintaining control of CSL. How far do you think he'd get?

This has nothing to do with Mr. Martin's ethics, which I'm sure are impeccable -- though it would have been nice if we'd been told that, as finance minister, he had been kept abreast of important decisions at the company, rather than have to find out, nine years after the fact, that the "blind trust" in which everyone thought he had placed his holdings was not so blind after all.

No one suggests that he took part in any decisions as finance minister that afforded preferential treatment to CSL. Nor is anyone suggesting he would as Prime Minister. But that's not the point. A conflict of interest can still exist, even if it is never acted upon. Indeed, the very desire to avoid any impropriety, or the appearance of it, can distort government decisions every bit as much as the contrary motive.

Mr. Martin's defenders argue that transparency is safeguard enough: With the press and opposition watching his every move, the future Prime Minister would never dare to act in a way that benefited his corporate interests. The Globe and Mail's Hugh Winsor, for example, noted that Mr. Martin owns a bus company operating between Toronto and Montreal, in competition with VIA Rail. But because this is public information, he went on, Mr. Martin could never cut VIA's subsidy, even though this would be to his financial benefit.

But he should be cutting VIA's subsidy! It's not just unfair to its competitors. It rewards inefficiency, it distorts consumer choices and it's money that could be put to higher uses.

This is exactly what some of us most fear. In how many other areas would Prime Minister Martin be deterred from acting in the public interest out of fear of being accused of furthering his own?