I think there's a hint of truth in his supposition though. The gun lobby enjoys significant popular support from the general public who want to buy guns, but they also receive support from the gun industry that want to sell guns. The intersection of these two interests is protecting Americans' right to buy guns from American gun manufactures. In this, the gun lobby has been effective.

However the gun lobby has been generally ineffective and uncaring when it comes to protecting Americans' right to import guns from other countries. Collectors like importing guns, but American gun manufacturers have little interest in that. For instance, the NRA doesn't seem very upset about the Norinco ban, even 20+ years ago when the political/strategic situation between America and China was not on the minds of many. Another example is 922(r) compliance concerning domestic/foreign part counts; notorious among gun collectors as inane, arbitrary and pointless. Yet there doesn't seem to be much drive from the American gun lobby to get this fixed.

It takes very little money to buy your politicians. Tens of thousands of dollars to sway their opinion, a few hundred thousand to buy it outright. The gun companies own a lot of your politicians.