Republican wars

First, trying to claim President Obama is blood-thirsty is laughable.

Second, since the Republican Party didn't even really come onto the national stage or hold the office of the Presidency until 1861, sort of a loaded question.

Third, all the above aside here ya go:

(All under the American Indian Wars, which can rightly be called a genocidal war)
 * Dakota War of 1862
 * Colorado War
 * Battles for Shimonoseki
 * Snake War
 * Red River War
 * Modoc War
 * Black Hills War
 * Nez Perce War
 * Bannock War
 * Cheyenne War
 * Sheepeater Indian War
 * White River War
 * Ghost Dance War

Other wars we were involved in that were initiated under Republican Presidents.
 * Shinmiyangyo
 * Second Samoan Civil War
 * Spanish–American War*
 * Moro Rebellion
 * Philippine–American War
 * Boxer Rebellion
 * Vietnam War
 * 1958 Lebanon crisis
 * Gulf of Sidra incident
 * Lebanese Civil War
 * Bombing of Libya
 * Iran-Iraq War (supplied Iraq weapons and intel)
 * Invasion of Panama
 * Persian Gulf War
 * Somali Civil War
 * Afganistan
 * Iraq
 * Second Liberian Civil War

Only one of these, the Spanish-American War, was declared war. Also of the actually declared wars, 80% of those were carried out under Democratic residents, and if you want to argue we should not have gotten involved in War of 1812, World War I or World War II (all under Democratic Presidents), be my guest.