Since the end of the Cold War, President Bush says Russia has tended to view the expansion of freedom and democracy as a threat to its interests.
Mr. Bush told reporters at the White House that the days of satellite states and spheres of influence are over, and Russia's attacks in Georgia have damaged its credibility.
"Bullying and intimidation are not acceptable ways to conduct foreign policy in the 21st century," the president said. "Only Russia can decide whether it will now put itself back on the path of responsible nations, or continue to pursue a policy that promises only confrontation and isolation."
Mr. Bush says he hopes Russia's leaders recognize that a future of cooperation and peace benefits all parties and he says a contentious relationship between Russia and America is in neither nation's interest.
Russian forces continue to control the Georgia city of Gori with tanks and military vehicles blocking access to Georgian authorities who have tried to re-enter the abandoned city. Russian officials told reporters they are busy providing humanitarian assistance.
Georgian President Mikheil Saakashvili told CNN Thursday that Russian troops occupy one-third of his country.
U.S. Secretary of State Condoleezza Rice was in the Georgian capital for talks with President Saakashvili in hopes of reaching agreement on a cease-fire that ensures the withdrawal of Russian troops from areas outside the breakaway republics of South Ossetia and Abkhazia.
President Bush will meet with Rice at his Texas ranch Friday evening for a briefing on her trip, which also included talks in France with President Nicholas Sarkozy. Mr. Bush says Rice, in Tbilisi, expressed America's wholehearted support for Georgia's democracy.
"The United States and our allies stand with the people of Georgia and their democratically-elected government," Mr. Bush said. "Georgia's sovereignty and territorial integrity must be respected. Moscow must honor its commitment to withdraw its invading forces from all Georgian territory."
Russian Foreign Minister Sergei Lavrov said the world can forget about Georgia's territorial integrity, as President Dmitri Medvedev Thursday met with leaders of the breakaway republics.
White House spokeswoman Dana Perino dismissed the Russian Foreign Minister's statement as "bluster" that Washington will ignore.
President Bush says some Americans may wonder why events in a small country halfway around the world matter to the United States. He says Georgia has become a courageous democracy since the fall of the Soviet Union, holding free elections and opening up its economy.
"Georgia has sent troops to Afghanistan and Iraq to help others achieve the liberty that they struggled so hard to attain," he said. "To further strengthen its democracy, Georgia has sought to join the free institutions of the West. The people of Georgia have cast their lot with the free world, and we will not cast them aside."
President Bush has ordered the U.S. military to begin a humanitarian relief mission in Georgia and he expects Russia to honor its commitment to ensure that all lines of communication and transport, including seaports, airports, roads and airspace remain open for the delivery of assistance and for civilian transit.