Not every so-called conservative or Republican exhibits these behaviors, but enough do that I bristle at being called "conservative" or confused with Republicans. They range from the small to the large, and I see them in conservative editorials and political speeches, on conservative web forums, talking to conservatives, etc.
1. Rank ignorance of economics. But this bugs me about everybody. The same people who say that government stimulus spending doesn't work (and it doesn't), will in the same breath advocate spending government money on sports stadiums and teams to "stimulate the local economy."
2. Confusing the "socialism" and "Marxism" with "statism." One can be statist without being a Marxist or socialist. Very few people, even many liberal Democrats, are actually socialists and Marxists, and most of the genuine socialists and Marxists are in academia or ensconced in government bureaucracies. Not many of them actually run for office (there are exceptions, like Bernie Sanders and Barbara Lee). You sound like an idiot when you call somebody a Marxist just because they are left-of-center. Even being a communist does not make one a Marxist, and (believe it or not) you can be a bona fide Marxist without being a communist. "No way!" you say? Yes way! Why not read Thomas Sowell's excellent book on Marx so you actually know what you're talking about? Conservatives are always attacking Europe and other countries with large welfare states or nationalized industries as "socialist," which is sometimes true and sometimes not. France has privatized water utilities. We have socialized water utilities. France has more nuclear power than we do. There are many things about so-called socialist countries which do not fit the socialist mold, and you make yourself ill-prepared to logically defend free market economics when you've painted everything with the same broad brush. Americans often mistake a large welfare state for socialism. However, social services are not necessarily the same thing as socialism, and you can in theory have a free market economy and a welfare state at the same time (though I don't recommend it), in the same way that an organism can be healthy and living and growing in spite of having an ailment. Part of the reason many other countries spend so much more on welfare state programs is because A) they don't spend much on defense and B) they often spend their welfare state money more wisely than we do, by which I mean they ration care and cut corners all over the place. Americans wouldn't put up with that, but generation after generation of them have grown up with rationed medical care.
3. Protectionism. Throw a rock in any gathering of conservatives and you'll hit somebody who on one hand claims to hate government interference in the free market, and on the other hand never met a protectionist policy they didn't like. They can say they aren't protectionists, like Lou Dobbs claims, but they are. They dig up arcane quotes from economists that they don't understand, dredge up discredited episodes in history, use misleading statistics that they don't know how to read, and good ol' bad reasoning to support their arguments for high tariffs, import quotas, worrying about "trade imbalances" and how to correct them, and nationalism (not to be confused with patriotism). Free trade (not "fair trade") is simply a good policy. "Fair trade" and protectionism aren't. End of story. No argument. I can respect people who disagree with me on most issues, but two schools of "thought" for which I have nothing but contempt are socialism and it's ugly twin, protectionism.
4. Conspiracy mongering about the NWO or globalism or some such crap. It doesn't crop up super-often, but it does crop up. Economic illiterates often accuse staunch free trade supporters of belonging to some NWO cabal wanting to impose one-world government, as if free trade has anything to do with that.
5. Seeing Biblical prophecy everywhere. Just stop. Stop embarrassing us. The Bible does not predict that something call the "AntiChrist" will rule the world, or that Europe will unite into one nation, or that a global government will form, etc. There is not a shred of Scripture to back up any of this malarkey. Reread Revelations. Notice how the word "anti-Christ" isn't actually in there. Revelations is about God's Kingdom. It is a prophecy that we will not understand until it has happened, in the same way that the Old Testament prophecies about Christ were not understood until after Christ came, died, and rose again. It is not to guide us, but to show us, after the fact, that God's Word predicted it.
6. Remaining ignorant of other countries and cultures. This goes hand in hand with unfounded assumptions about other countries and cultures. Once on a conservative web forum, somebody posted pictures of Sikhs visiting Obama at the White House for a function. All the conservatives saw the turbans the Sikhs were wearing, immediately mistook them for Muslims, and went railing on about how Obama is a secret Muslim and cavorting with the enemy. Why not wear a dunce cap while you're at it? This type of behavior is typical of a great many conservatives. I talk to conservatives who seem to think that every other country in the world lives in poverty and oppression, seemingly ignorant of what it is actually like to live in Australia or France or Norway or Singapore.
7. Mistakenly assuming that the US has anything like a free market health care system, and then trying to defend it on those grounds. No objective observer who understands economics would mistake the US health care system, with it's 50% (give or take) government funding, myriad rules, licensing restrictions, regulatory bodies, and onerous requirements put on insurance companies. For some reason, too many conservatives try to defend the US health care system and attack foreign socialized systems. A few things wrong with this: the US health care system is a government bureaucrat's dream, not a free market, and not all socialized or government universal health care systems are the same, so the same arguments against, say, Britain's NHS won't fly against Singapore's much-better government universal health care system, which is run much more like a business and less like a government bureaucracy. Again, as with protectionism, I run into conservatives who claim to love the free market but want to protect (rather than reform or abolish) Medicare, Medicaid, etc. A big mistake that everybody makes is that health care cost rises are simply bound to out-pace inflation in perpetuity, rather than trying to reform the system, another huge mistake is to assume that health insurance (with all of its problems) and health care (with all its problems) are one and the same issue. The health care industry is a perfect place for free market boosters to point out the flaws in government intervention, yet this rarely happens. I have never read a conservative editorial pointing out how licensing laws increase the costs of health care, sometimes drastically.