撒切尔夫人在何时何地说过“将来世界上只有两个大国，一个是美国，一个是中国。”貌似中文搜索里找不到？

因为撒切尔根本没有说过后一句话，所以没有原始的出处。
用膝盖想想好了，撒切尔夫人这种政治家，会对中国如此浮夸、如此浅薄地说三道四？她会对历史这么可怜地无知？这种话说出来没有贬低中国，贬低的是她自己和英国人。
第二句话和第一句话完全是矛盾的话，根本是南辕北辙的两个内容，怎么会出自同一人对国际政治的评价？
后面这句话的真正出处，是一小撮骨子里自卑又可怜里的冥运或者轮子，或者是神经兮兮的公共识字分子，他们恨中国，厌恶中国，但是自己又不敢以真面目共公开说，所以搞了没法考证的“出处”，为了增加话的份量，撒切尔就“被”开口了。

第一句话，找了一阵，发现她也没有说过，但是有类似的言辞。有两篇她关于中国的演说
第一篇是：《中国崛起：史诗般壮丽的20世纪中国》（Margaret Thatcher 《China Rising: The Epic History of 20th Century China》）网上有视频。
另一篇是在美国胡佛学院的演说《时代的领导》《 the Hoover Institution ("A Time for Leadership")》，这个演说有她的全文。关于中国她是这样说的“
China.....
We are apt to say - and I say myself, when I forget - that victory in the Cold War meant the collapse of communism. But, of course, that is not strictly true. Indeed, one communist power has actually benefited by the implosion of the Soviet Union. China is now the main candidate to become a superpower, and its intentions and capabilities are rightly the subject of intense debate.
China is certainly a rising power - its already vast population is growing, so is its economy, and so are its ambitions - all three in contrast to those of Russia. And still more than Russia, China's past history and present ideology suggest that for the foreseeable future it remains deeply hostile to the West.
The argument that economic progress will automatically change that is flawed. It is certainly true that pressures for democracy will increase as living standards rise. But the ruling elite in China, which uses the slogans, apparatus and methods of communism to stay in power, is not going to go quickly or quietly. It cannot afford to embrace democracy, and at the moment it does not need to. It is, after all, able to repress dissent without much difficulty. It has even perfected a system, combining enterprise, corruption and slave labour, that allows it to benefit from growing prosperity. And I would like here to pay tribute to Harry Wu who courageously exposed that wicked system.
Communism with "Chinese characteristics" still has many of the characteristics of communism. Yet for all its abuses, China should not be isolated: it is far too important for that. Indeed, it should be drawn further into the global economy. But nor should it be appeased, particularly over Taiwan.
China will not become a superpower to match the United States - at least, not while it is held back by the dead weight of socialism. But it is a potentially hostile regional power. In the long run, democratic India may emerge as a counterweight. But today and for the foreseeable future, it is Japan which must be America's strategic partner in the region. Keeping that partnership alive and well is the fulcrum of stability in the Far East.

撒切尔夫人在1998 年说: “将来世界上只有两个大国,一个是美国,一个是中国。” 我们亲手结束300 年落后历史 用150 年时间融入世界,成为世界政治大国。