First a small bit of news: As The Fix’s Rachel Weiner reports, President Obama has a new ad that knocks down the out-of-context “didn’t build that” attacks. Meanwhile, plenty of good stuff to get to:

1. An excellent story by Alec MacGillis about what political scientists are studying in this year’s ads — and why you can expect lots of potentially effective attack ads from the Obama campaign.

2. Don’t pay any attention to polls showing Libertarian candidates doing well; as Dylan Matthews reminds us, early polling on third-party candidates is pretty meaningless.

3. Could drought hurt Barack Obama this fall? Political scientist Larry Bartels says: Yup, it really might.

4. David Frum points out that the Democratic reaction to Aurora makes it even more clear that Fast and Furious conspiracy theories are, well, just incredibly stupid.

5. And Charles Lane points out Europe’s role in U.S. gun culture.

6. Meanwhile, David S. Bernstein argues that exactly one thing is proven to reduce gun violence — and it’s part of the Affordable Care Act.

7. Great item by Kevin Drum about the new (and very much false) conservative talking point that government had nothing to do with the creation of the Internet. He notes that it’s impossible to imagine mainstream liberals making the opposite argument, that the private sector had nothing to do with the creation and growth of the Internet. (And yes, it’s another example of lazy mendacity.)

8. Jonathan Cohn tries once again to explain just how radical the Romney (and Ryan) budget plans really are: In short, Romney wants to weaken or eliminate many of the supports on which all Americans, including small business owners, survive. You can make a pretty strong case that, in such an environment, building a business would be much more difficult than it is today.

9. Adam Serwer also surveys how Romney’s vision of “Galtian ubermensches” contrasts with the actual humans that Romney picks as examples.

10. Are the Bain attacks working? Steve Kornacki considers that question.

11. On Romney’s foreign policy speech today: Heather Hurlburt counts five obvious lies.

12. I very much liked E.J. Graff’s appreciation of Sally Ride, including just how distant the concerns of the 1980s feel. One point she didn’t make: doesn’t “partner of 27 years” already sound almost dated, too?

13. And a good Matthew Dickinson post laying out the political science view of campaign effects: both why they are real but also why they are usually smaller than you may think.