Blaming Corruption

According to a poll on the front page of today's El Universal, 47 percent of Mexicans said that corruption is the principal problem facing Mexico's oil industry. Twelve percent said lack of resources for exploration (which I interpret to mean lack of cash for deep-water wells, rather than lack of exploitable oil fields) is the biggest issue, while 11 percent said that it's bureaucracy, and another 4 percent said it was because of Pemex's excessive tax burden. There are and have always been a wide range of issues limiting Pemex, including all of those mentioned in the poll. But without ignoring the impact of corruption and the rest, isn't the basic issue now more than anything that Mexico has no oil? If you reduced the tax burden to zero and banished corruption at Pemex, would the short-term challenges of Pemex be any different?

That leads me to the following question, which isn't rhetorical: historically, has corruption been more of a problem at Pemex than mismanagement? My understanding of Pemex is pretty superficial, but from what I've read, it seems like the company has basically functioned in the past thirty years as it was set up to function, which is to say, it was sucked dry.