America Denis StauntonYesterday's unravelling of a Senate deal to overhaul America's immigration system highlights the political delicacy of an issue that has brought hundreds of thousands on to the streets in recent weeks and seen schools ban national symbols in an attempt to defuse tensions.
The Senate compromise collapsed after conservative Republicans sought to introduce amendments that Democrats feared would undermine an attempt to give millions of illegal immigrants a chance to become US citizens.
Republicans are deeply divided. Economic liberals view immigrant labour as essential to many US businesses while cultural conservatives, who see America's porous borders as a security threat, want to deport all illegal immigrants and build a security fence along the border with Mexico.
President Bush has sought to embrace both wings of the party, calling for stronger borders but backing a temporary worker programme that would allow millions of immigrants in the US to legalise their status.
Conservative Republicans facing elections in November are tempted to take a tough line on immigration, not least because they would prefer to talk about immigration than about Iraq or the domestic record of this unpopular administration. More than 90 per cent of Americans regard immigration as an important issue and many, particularly in southern states, complain that illegal immigrants are clogging hospital emergency rooms and filling schools with children who cannot speak English.
However, Mr Bush and his political advisors fear that too harsh an approach to immigration could alienate the Hispanic community, which accounted for nearly 14 per cent of the US population in 2004, a proportion that is expected to double by 2050.
Hispanics are already the largest minority in America, overtaking African-Americans in 2000 and in California, they account for one in three of the population. Republican lobbyist Grover Norquist warned that if Republicans don't back a path to citizenship for illegal immigrants, the party could lose the Hispanic vote, just as it lost the Catholic vote for almost a century.
Last month's massive pro-immigrant demonstrations took Washington by surprise, alerting both parties to the political potential of the protests. Angelica Salas, executive director of the Coalition for the Human Rights of Immigrants, declared that the marches marked the dawning of a new era of political influence.
The demonstrators, students, religious leaders, and trade unions as well as immigrants, were provoked into action by an immigration Bill approved by the House of Representatives earlier this year that would make felons of illegal immigrants and those who offer them help, including shelter or advice.
Some Democrats believe their party could benefit in November if the Senate fails to introduce a Bill before then and the House Bill is perceived as the Republican party's position on immigration.
Many analysts draw parallels with California's Proposition 187 in 1994, which established new rules on the registration of illegal immigrants, and denied them public education and other social services. The Republican-backed measure was approved in a popular ballot by 59 per cent to 41 per cent, but it has often been blamed for the subsequent decline in Republican fortunes in California.
In fact, first-generation immigrants supported the initiative by 54 per cent to 46 per cent and three out of five third-generation immigrants supported it. However, Hispanic support for California Republicans fell sharply, and Mr Bush and his chief political strategist Karl Rove believe the risk of losing such support on a national scale is enormous.
A national day of action in support of immigrants next Monday is expected to attract millions on to the streets of more than 60 American cities. But as senators and congressmen return to their constituencies for a two-week Easter break, they will hear other voices calling for a crackdown on illegal immigrants and on the businesses that employ them.
The president's role in brokering a deal between the two wings of the Republican party could be crucial, but many fear that Mr Bush may have exhausted his political capital to the point where few legislators are prepared to listen to him.