Chrysler Corporation had a flat tire and the federal government's repair truck put it back on the road. It has been a spectacular success. Instead of going broke, this month Chrysler paid back the last $813 million of its $1.2 billion federal debt. Few things in the industrial line have been so sensational in a long time.
The question is: Now what? The answer affects economics, industry, and politics.
If the government helped Chrysler, why not other corporations and, indeed, whole industries? That's what the depression-era Reconstruction Finance Corporation (RFC) did in the 1930s. That's what the Japanese government does for its spectacularly successful businesses. In fact, that's what many legislators want to institute in Washington, what another large group of industrialists fear is ''government interference,'' and what the Reagan administration rejects.
Some see the situation evolving into a fundamental issue of ''national industrial policy'' (NIP), with Republicans and Democrats on different sides and the administration's so-called Reaganomics challenged by a rival philosophy of government planning, assistance, and aid.
Here are instances recently where public assistance has played a big role:
* Conrail, formed by Congress to take over six bankrupt Northeastern railroads.
* Lockheed Aircraft Corporation rescue.
* Bailout of New York City from near bankruptcy.
* Chrysler recovery, with Congress guaranteeing $1.2 billion in loans.
Instances like these have raised all sorts of questions - economic, practical , and ideological. Is it time for Washington to accept a new policy - NIP - and a closer relationship between government and business at a time of world technical change?
Herbert Hoover launched the Reconstruction Finance Corporation; Franklin Roosevelt grabbed it. A federally backed corporation distributed $25 billion in 25 years to banks, railroads, corporations, and farmers. Congressmen such as Rep. Claude Pepper (D) of Florida would revive it today.
The ideological line, however, arises. How far should federal aid go?
President Reagan says his policy is about right. Some aid in emergencies, he says, but a minimum of regulation. Big industrial groups support him. Rep. Edwin V. W. Zachau (R) of California with a reputation as high-tech spokesman in the industrial sphere, also backs him.
Democrats offer counterproposals. It's possible that the whole party, and its presidential hopefuls, will accept a restatement of industrial policy as a counter to Mr. Reagan.
New York Democrat John J. LaFalce, chairman of the House Economic Stabilization subcommittee, wants a coherent national industrial policy. Some Democrats would create an ''Economic Cooperation Council'' to analyze problems of specific industries.
Rep. Stan Lundine (D) of New York would revive an RFC-type organization, a ''National Industrial Development Bank'' that would make low-cost loans to key industries.
President Reagan and many businessmen are weary of such proposals. The 1984 election, most say, will turn on the condition of business and economic recovery next year. Democrats propose hearings to outline a party plan. Republicans are suspicious. They sense a new drive at regulation. There is also rivalry between ''smokestack'' industries, such as steel and automobile, and the new, high-tech industries. Before either group accepts a new industrial policy, they want to know what it will cost to get federal assistance.