The US Democratic Party is plagued by Bipartisanship. They very often go along with Republican policies, although the reverse is not usually true. That's why they are virtually the same parties. They may be dynamic, but they move in the same direction all the time. There is also a distinction between the legislative and the executive. The US congress does not always follow the Presidential line, even though they are the same party. Both parties tracking popular opinion is also a sign that they are the same: they follow public opinion (shaped by the corporate press, btw, or just another form of brainwashing). Both will try to get the most votes, not just a minority of votes that suit their policies. On foreign policy, they are virtually the same. Democrats start as many wars, and overthrow as many foreign governments as Republicans in power. Most congressmen go on their Israeli (paid) pilgrimage every year to pay their hommage to Bibi, the king of the jews.