Most of the right wing's favorite anti-liberal slanders are rooted in some deeply-held—and deeply wrong—assumptions about who liberals are, and what we believe.

Here's a basic set to get you started. Tuck it away in your bag with your Xanax and Maalox, and apply (liberally, of course) as needed.

1. Liberals hate America.

For the record: Liberals love America. In fact, what makes us liberals is that we actually read and believed all those pretty words in the Declaration of Independence about "life, liberty, and the pursuit of happiness," and in the Bill of Rights about freedom of speech, religion, assembly, privacy, and all the rest of it.
We're idealists that way. We want to live in the country the Founders described. We believe that the nation's founding documents expressed a uniquely powerful moral contract between the people and their government, and an audaciously positive vision of people's ability and competence to shape their own future. When we get annoying and whiny, it's usually because we believe so much in America's astonishing promise—and our own responsibility for realizing it—that we're sorely disappointed when the country falls short of that standard. We really want to believe we can do better.
Conservatism, by contrast, tends to take a dim view of human nature, prefers hierarchy to liberty, and isn't completely convinced people can or should be trying to contravene the will of God or their betters by trying to arrange their own futures. This tends to lead to a selective reading of the Constitution (as well as the Bible), and—as we've seen in the Bush years—a far more flexible attitude toward its interpretation.
The proof, however, is in the history—and it's pretty irrefutable. America's greatest moments of progress, generosity, and moral strength occurred when the country stuck most closely to its progressive ideals. We loved America so much that we freed the slaves, passed child labor laws, built schools and colleges, gave the vote to women, enacted civil rights laws, rebuilt Europe after a war we helped win, and put a man on the moon. All of these were progressive projects—and all were fought tooth and nail by conservatives in their time, simply because they feared change and saw power as a zero-sum game. Yeah, we sometimes overshoot and miss—but you can't argue with the daring scope of our dreams. We're every bit as American as our conservative friends and relatives, and have been since the day the Declaration was written (by a liberal, in fact).

2. Liberals want to leave us defenseless in the face of evildoers around the world.

The big disconnect on security issues begins with the fact that we have a far more expansive definition of "security" than conservatives do. And, perhaps, a broader sense of what the actual threats are, and what can be done about them.
When conservatives discuss "security," they're usually thinking in terms of solving all our problems by sending in more guys and gals with guns. The flip side of this that they tend not to give much credence to real threats that can't be fixed by guys and gals with guns.
But as progressives, we know that the country's financial crisis is a security issue. And in a world of superbugs and epidemics, universal health care is a security issue. And global warming is, plain as day, a looming security issue (and the Pentagon agrees). We also know that sending in the Marines, hiring more cops, and taking off our shoes at the airport won't begin to address some of our most terrifying problems. Real-world security is far more complex, and requires a much wider range of solutions, than most conservatives are willing to consider.
3. Liberals hate the free market.

If that's so, why does everyone down at the Apple Store know my name?
The operative word here is "free." Liberals believe wholeheartedly in the amazing power of markets to deliver all kinds of important goods. But we've also noticed that some of the deepest human goods of all—a strong family, a caring community, a healthy environment, safe food, clean water and air, and time to enjoy them all—are assigned no economic value at all in unfettered markets. If we want to protect the value of things that money can't buy (and even conservatives will usually agree that such common goods exist, and deserve to be protected), then we need to put some restrictions on markets so they can't encroach into those areas.

4. Liberals hate our troops.

We love our troops. We love them so much that we want them brought home safe and sound to their families, as soon as possible.
This one's almost depressingly easy. Who blocked the new GI Bill because it might encourage troops not to re-up? Who refused to increase VA funding? Who oversaw last year's debacle at Walter Reed? Who is making soldiers buy their own body armor?
News flash: it ain't the libruls. Putting a yellow ribbon decal on your car is not enough. Making sure our troops have everything they need to do their jobs—and keeping our promises to them when they get home—is putting our money where our mouth is. Liberals have been there doing the heavy lifting from the start, while the conservatives in government have been nowhere on the scene unless there was a photo op involved.

5. Liberals are a bunch of elitists who hate decent working- and middle-class Americans. opposed to those sainted corporate men-of-the-people who fly around in private jets and pull down eight-figure salaries while closing plants and cutting 10,000 jobs at a time. That's what real populism looks like, you betcha.
Liberals are funny people. We think that sending well-paid American jobs overseas is a bad idea. We think the minimum wage should be big enough to cover life's necessities, with some left over. We think it's insane that over half the bankruptcies in the country are due to lack of adequate medical insurance. We think everybody who has the grades should have a shot at college. And we believe that middle-class prosperity is absolutely essential for maintaining a healthy democracy—because history (via Kevin Phillips) has taught us that no democracy that's tolerated our current levels inequality has ever survived for long.

6. Liberals are against "family values."

This is one of the biggest disconnects between us. As George Lakoff has pointed out, conservatives and liberals have very different ideas about what families look like, how they function, and what rules they should run under. The problem is that liberals are quite willing to recognize the conservative model as a legitimate and valid way to do family, even if we don't always agree with it. But when conservatives look at liberal families and their patchwork of made-up arrangements, they see a chaotic free-for-all that doesn't follow any of their strictly mandated rules of family organization—and thus doesn't qualify in their minds as any kind of "family" at all. We think it's creative and flexible. They think it's unstable and scary.
So it comes as a considerable shock to conservatives when you point out that progressive areas of the country have significantly stronger families, by almost any metric you can imagine. They have lower rates of divorce, teen pregnancy, infidelity, drug abuse, domestic violence, and juvenile delinquency than the more conservative areas do. Massachusetts—the first state to offer gay marriage—also has the lowest divorce rate in the country. They like marriage so much there they think everybody should have a shot at it. Liberals believe in family. We take our marriage vows just as seriously as conservatives do. We love our children just as much. Our families are at least as successful and happy as theirs. This shouldn't be a matter of debate; but it will continue to be one as long they refuse to believe that our families are just as healthy, valid, and sacred to us as theirs are to them.

7. Liberals want to raise our taxes.

It all depends on who is the "our" in this scenario.
If your dinner companions are well-off enough to be bringing in over $250K a year, there's no point in finessing this. Their taxes probably are going up. The only comeback is that between Clinton-era tax cuts, the housing bubble, and the hot stock market of the past 15 years, they've probably made so much money that it's time to start giving some back to the nation that made their boon possible. (Refer back to #5: they almost certainly didn't make that pile without at least some government help.)
If 's nobody at the table fits that happy description, then according to Obama's plan, they're going to get a tax cut. Sure, they're not going to believe it until they see it (and, quite possibly, not even then); but it's not an argument they even want to have until after an Obama tax plan is passed and the actual results are in. Remind them also that there's just no way to pay for a $600 billion war and a $700 billion bailout (and that's just the current cost on both fronts—they're likely to soar in the future) without somebody somewhere paying some more taxes. The bill for the war alone currently stands $5,000 per American household; the bailout may cost that much again, depending on how much of the money the government can recoup. The GOP went shopping on our credit card—and now it's time to pay our share of the bill.

8. Liberals are Godless—and therefore, amoral.

This often sounds odd coming from people who raised you, who generally like you, and who usually think you're a fairly sound citizen...well, apart from that weird liberal thing. One good comeback is to personalize that accusation: Do you really think I'm less moral than you are? Seriously? In what way? Hmm. (It's good if you can resist the temptation to say: Gee, it must have been the way I was raised.)
Another twist on this: I'm liberal because you made me that way. You dragged me to church, where they taught me to love my neighbor and care for the poor and sick—and I became a progressive because I took the things you taught me to heart.
If personalizing the argument won't work with your crowd, go general. A lot of progressives are deeply religious—and our politics are guided by our religious faith. Evangelical churches are getting involved with environmentalism, poverty, and human trafficking—all issues where liberals have been active for decades. It's good to have the extra hands on board.
It's also true that a lot of progressives aren't religious. Unfortunately, many conservatives equate "secular" with "having no moral code whatsoever," since they honestly believe that nobody can possibly behave themselves. Rejecting God means you refuse to follow His rules—which, according to their logic, can only mean that you hold nothing sacred and don't recognize any rules at all.
Call this out for the wrongness that it is. All non-religious progressives have things they hold deeply sacred: family commitments, community obligations, professional responsibilities, the Constitution, social and economic justice, the earth and its systems, the idea of democracy, the dream of a peaceful future. Those things form the basis of a demanding internally-driven moral code; and it's not uncommon to find secular progressives who live more uncompromisingly moral lives than many overtly religious people.

9. Liberals don't believe in personal responsibility.

Again, there's a definitional disconnect at work here. Conservatives tend to use the rule of law to enforce traditional morality and social hierarchies, which usually means light treatment for those at the top, and harsh penalties for those at the bottom. Liberals tend to use the rule of law to maintain some semblance of fairness and equality, which means that those who have more should be given sentences proportional to their greater wealth and power; and those with less should be given a more gentle hand. Naturally, each side finds the other side's reasoning and criteria appalling.
But there is common ground. The bare fact—which everybody at the table may agree on—is that in present-day America, nobody is happy with the way justice is being doled out, and people all over are getting away with things no civilized nation should allow to slide by. Absurd leniency abounds on both sides. You can either argue over whose side is getting the worst of it; or you can simply agree that the system is broken all over, and move on to the pumpkin pie.

10. Liberals are wimps.

Conservatives like to caricaturize liberals as being soft in all the places our society values toughness. Our refusal to adhere to any dogma must mean that we're soft in our convictions. Our reflexive open-mindedness is often derided as evidence that we're soft in the head. Our persistent and gentle insistence on humane government is evidence of hearts too soft to set hard boundaries or do what must be done. And all of this together makes it easy for them to portray us as a mushy bunch of feckless, effeminate intellectuals lacking in cohesion, backbone, focus, or purpose.
But you can only believe this if you don't know anything about the history or reality of American liberalism. The Constitution is, itself, a liberal document—the ultimate expression of Enlightenment principles. In every decade since the republic was founded, progressives have stepped up and put themselves on the line to further the purposes of government laid out in the Preamble. We're heirs to the people who fought and died to free slaves, organize unions, give the vote to women, end child labor, protect family farms, enact civil rights laws, and preserve our environment. Some of the boldest, bravest Americans in history— Harriet Tubman, Susan B. Anthony, Frederick Douglass, Teddy Roosevelt, Cesar Chavez, and of course Dr. King—have proudly called themselves "liberal" or "progressive."
Progressivism couldn't have survived and thrived if we were half as weak and indecisive as conservatives like to think we are. Our progressive forebears were not fearful people. Nor did any of them seem to be bedeviled by a lack of conviction. "Mushy" or "feckless" are about the last words I'd use to describe any of them. ("Stupid" isn't anywhere on the list, either.) When you sign up to become a progressive, this is the legacy you take on, and from then on attempt to live up to. It's not God's job to make the world a better place. It's yours. This has never been work for the faint of heart, mind, or spirit—and in this era of conservatism gone rotten, it still isn't.