@ehBeth,
EhBeth,
You are making a couple of basic logical fallacies.
First, you can't dismiss key differences by listing similarities. There are a lot of ways that a frog is like a dog. They both have lungs, 4 legs a heart, eat food, etc. etc. etc. In fact I could even list countless ways that a frog is like a tree (dna, respiratory process, cells etc. etc). This doesn't prove anything. You are absolutely correct to point out the similarity of Obama and Bush when it comes to the Afghan war. This doesn't change the differences in social programs, civil rights, equal pay and countless other issues.
The way to prove differences or non-differences you need to look at the facts on that issue. And in critical issues for today like same sex marriage, health care, immigration reform and equal pay for women there is a huge, demonstrable difference between Democrats and Republicans. You can simply look at votes and rhetoric from political leaders to see this.
Nor can you say because 3 Republican congresspeople (out of hundreds) voted for theLilly Ledbetter act for fair pay for women, that the Democrats and Republicans are both in favor of it.
The equivalency fallacy is strong. But it doesn't make logical sense in the face of party line votes.