Rand Paul's entry into the 2016 Republican presidential primary is good for the GOP. I won't proclaim that Paul, 52, has the gravitas or character to occupy the Oval Office -- that remains to be seen -- but I do believe that all the other Republican hopefuls should watch and learn from Kentucky's junior senator. His take on issues could make independents and Democrats take a second look at a party where they have not felt welcome.

Paul describes himself as "libertarian-ish." He's not an apologist for the GOP. "It seems to me that both parties and the entire political system are to blame," Paul said in his campaign kickoff speech in Louisville on Tuesday. "Big government and debt doubled under a Republican administration. And it's now tripling under Barack Obama's watch." Many Republicans wonder why they send to Congress candidates who promise to reduce the size and scope of government yet government keeps growing. This rhetoric plays with the party's base.

Paul's criticism of excesses in the federal government's war on drugs should appeal to young people and African-Americans. Paul believes "any law that disproportionately incarcerates people of color" should be repealed. He quoted Martin Luther King Jr.'s criticism of "two Americas," one with opportunity, the other scarred by "daily ugliness."

Paul has supported legislation to reform draconian mandatory minimum sentences. He is a proud co-sponsor of a bill to reclassify marijuana as a Schedule II drug and to prohibit federal prosecutions of medical marijuana dispensaries in states that have legalized medical use. Americans are moving toward support for legalizing recreational use of marijuana. On this issue, Paul has put himself to the left of the Obama administration.

Paul is comfortable in the digital world. He tweets. His campaign takes bitcoins. Most importantly, he understands how the sharing economy has ignited an entrepreneurial spark in young adults.

Do I have issues with Paul? Absolutely. He's a first-term senator who thinks he can run the country. He is prickly with the press. Paul sounded very much like Obama circa 2008 Tuesday when he said, "I believe we can have liberty and security, and I will not compromise your liberty for a false sense of security, not now, not ever." It's foolhardy to think that there is no risk whatsoever in curbing surveillance.

In 2009, Paul told students at Western Kentucky University that "9/11 became an excuse for a war they already wanted in Iraq," referring to the Bush-Cheney administration. He tried to end U.S. foreign aid to Egypt after the military coup that deposed President Mohammed Morsi -- even though the new government proved to be a stabilizing force in the region.

Since then, Paul has moved from away from the knee-jerk noninterventionism of his father, libertarian icon Ron Paul. Events forced him to change. In 2007, Paul said Iran was not a threat to the United States. Now he sees the threat from Iran, and he supports foreign aid for Israel.

"He's gone to the edge of where he needs to be," opined Rand supporter John Dennis of San Francisco. Seven years ago, Paul "was an ophthalmologist" doing laser surgeries, Dennis noted. "Now's a candidate for president." Indeed, he's the most interesting GOP candidate for president.