Immigration as a political issue

I don't follow politics in the UK very much at all, but from the little I've seen and heard, the leader of the UK Conservatives appears to be manipulating the public's fear of "uncontrolled" immigration. I say manipulating because I could say from common sense that he's not playing to policy wonks who doubt the social and economic benefits of "uncontrolled" immigration - but to feelings of nationalism... that many Brits still feel after they lost such a vast and powerful empire. That's the practical effect at least.

Now of course, it would be silly to say that bringing up issues in relation to immigration is racist. That simply isn't the case, however, it still makes me a bit nervous when some politicians talk about immigration in general, in a negative context, even though that isn't usually their intention. In a perfect world, bringing up the issue would give me no worries at all, but in practice, it appears as if it's often brought up only in order to spread fear. For example, I felt a bit uneasy when George W. Bush introduced the gay marriage constitutional ammendment last year, because it seemed as if he was doing so, in part, to manipulate fears. Again, he might've done so with good intentions as well, but the fact that it was also filled with added political motives to manipulate fears against gay marriage and (for some) gays in general annoyed me.

Most immigrants who come to Canada, don't feel as if they've arrived here easily. They appreciate the fact that they're here, and most of them struggled to get here. I believe that same feeling is present amongst the United Kingdom's immigrant community. Immigration does not play a part in the collective memory of countries such as France, but countries in the Anglosphere generally tend to have such a tradition where their nation is seen by citizens as a refuge for others.

I hate to complain when an issue of public policy is used for "political purposes" since that would seem to be a pretty strange complaint... but when the issue of immigration is used disingenuously to exploit fears instead of rational/well-meaning concerns, then I'm incapable of supporting such a party who will do such a thing... not because of what they're saying exactly, but because of the indirect, but still intended effect of their words.

I don't know EXACTLY how a political party would raise concerns regarding immigration in a manner in which I would find okay, so that's really the problem... Is there a way to bring up the issue without making immigrants and second-generation Canadians, particularly visible minorities, feel uncomfortable?

I guess it would have to be done in a way that stresses the contributions of immigrants in general vs. the "exception" of some immigrants who don't fit into the rule of positive contributions.

Even then, that isn't really necessary at the moment, I don't believe in Canada at least, and even in the UK. Economic growth rates are seemingly at the highest levels in both countries since the 1960s or 1970s. So surely, immigrants can't be scapegoated for economic miseries?

If any of you have watched Lou Dobbs Tonight on CNN, you have witnessed a man who manipulates fear against all kinds of immigration (legal, but mostly illegal) every single day, while neglecting all their accomplishments in the face of an economic turnaround and steady economic growth. Even though his main stress is on illegals, I just find it uncomfortable to watch.... just because of the sentiment he's playing to....