U.S. Secretary of State Hillary Clinton is weighing in on NATO and the uprisings in Syria and Libya as she tours Africa.

Secretary Clinton Saturday said Syria is engaging in “horrific, revolting” attacks against its people to repress the uprising there. But in a television interview, Clinton said the U.S. was not planning to intervene militarily as NATO is doing in Libya.

The secretary said the crucial difference was that in Libya, the Arab League asked for international military action. But in Syria, she says regional leaders are working “behind the scenes” to negotiate an end to the violence. Clinton said the U.S. listens closely to what people “in the neighborhood” say.

Clinton was in Tanzania Saturday, the second stop on her five-day trip to Africa. While there, she is scheduled to hold talks with President Jakaya Kikwete before traveling to Ethiopia, where she is set to address the African Union with remarks expected to focus on Libya.

In Zambia earlier Saturday, Clinton reiterated Defense Secretary Robert Gates' warning that the NATO alliance must “share the burden” of responding to threats. Clinton said she fully agrees with Gates that all the NATO nations must invest adequately in defense.

Gates's comments had come a day earlier during his last major policy speech before stepping down as defense secretary. Gates warned the U.S. would not continue to subsidize NATO members who are not “serious and capable partners.”

Gates noted that only a third of NATO members have had the resources to mount strikes against Libya's leader, Moammar Gadhafi, even though all 28 members voted to authorize the mission.

At a forum with U.S. and Zambian business leaders, Secretary Clinton also urged American companies to invest in Zambia, citing its 11 years of economic growth.

She said the U.S. wants a relationship of partnership, not patronage; of sustainability, not quick fixes. Clinton says the U.S. wants to establish a strong foundation to attract new investment and open new businesses.